VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: fspGTD on November 07, 2004, 01:49:20 pm
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While I had a head off of the engine and a scrap head in the garage, I decided to see how a long-runner A2 gasser intake manifold and an upside-down flipped exhaust manifold and turbo would look bolted onto the head in the engine bay...
pics of the long-runner A2 gasser intake manifold:
(http://www.imagestation.com/picture/sraid147/p244ab65027ed77b8c66ef6ad3454d71e/f6280b55.jpg)
(http://www.imagestation.com/picture/sraid147/p280b37982b01a33fc636290c63b468d4/f6280b5f.jpg)
... looks like there is tons of room!
And here is the turbo exhaust manifold flipped upside down. There are some ribs cast into what is the upper surface below that would need to be ground off in order for the gasser intake manifold to fit, so here I have it pictured by itself in the car (without the intake manifold)...
(http://www.imagestation.com/picture/sraid147/p24f2f0ca1344ab652671263cce92c554/f6280b63.jpg)
shift linkage interferes with the turbo compressor housing, but looks like the shift lever if bent "flat" could be modified to work... also, the compressor housing would need to be clocked for more clearance:
(http://www.imagestation.com/picture/sraid147/p4f363e7134c2dcb02dbffa24c2dce8cd/f6280b58.jpg)
... also the air intake system would need to be re-done as it's on the opposite side of the block.
The center section of the turbo would also need to be clocked to put the oil supply at the top, and oil return at the bottom. There looks to be enough room for the oil return. The turbo downpipe would need to be re-done but it looks like there might be just comfortably enough room:
(http://www.imagestation.com/picture/sraid147/p65123d828ca51f53957bf69ea6f26a95/f6280b66.jpg)
...all in all, seems like a pretty big job all for "just" a long-runner intake manifold. You can see why if I'm considering all this, I'm seriously considering as an alternative a custom-fab'ed long-runner intake that would fit with the turbo in the stock location (which as you may know on transverse-engine mount application, is up high and very tight against the head, leaving very little room for the intake runners.)
Handling this turbocharger, I'm sort of amazed how heavy it is. I've got to weight this thing... there could be a positive side effect to doing this which would be just getting the turbo mounted a few inches lower (lowered the center of gravity.)
By the way, the A2 gasser intake manifold has runners that are just about the same length as the naturally aspirated diesel intake manifold! If I were to successfully relocate the turbo with the exhaust manifold flipped upside down, it might not be that hard to get the A1 gasser intake manifold to fit (which has comparably shorter runners vs the A2) and do a comparison.
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Jake, I don't know if you've had a close-up view of audi 5000 (turbo, i think) intake manifolds, but they've longer runners than the A2. You'd need to cut a runner off to convert 5 to 4 banger though. I believe they have a circular inlet hole as well, which would be easier to work with.
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Looking good, but long runners on gassers are usually mostly for low end / midrange. For best top end power one needs relatively short fat runners, although not as short as the TD ones, if you can call them runners at all! If the ports match up nicely, this one you have pictured now looks VERY good but I wouldn't expect any gains from going even larger.
Also make sure you heat shield the manifold and the turbo properly ; such a large intake manifold may otherwise get cooked and heat the charge air!
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i'm guessing the whole point is to improve off-boost performance, in which case, somewhat longer should be better. If the wastegate measures boost from the intake manifold, rather than from the compressor scroll, it'll compensate for any flow restrictions at higher rpm. (not that I'd suspect many diesels of revving high enough to make a long runner intake become a restriction)
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Jake, I bet an intake off an A1 GTI would work even better in a racing application. Stan
(http://home.earthlink.net/~rps1976/Images/Diesel/IntakeEndView.jpg)
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A good ported A1 intake would be hard pressed to outflow a stock A2 intake manifold....so I'd vote for the A2 manifold.
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do you think about a 2.4d intake manifold? from a 5 cyl......
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Either way guys (A1 gasser, A2 Gasser, Hacked-off-runner Audi5kTD, or Digifant/G60 which has same runner length as A1 gasser but larger runner diameters)... these manifolds are pretty cheap at the wrecking yard and once the turbo is out of the way, could be swapped pretty easily (IE: intake manifold bolts are accessible without removing the turbo.) The hardest thing about swapping from one gasser-style intake manifold to another would be hooking up the boost tube if it were on the opposite end.
The most difficult part of this job would be would be getting set up by relocating the turbo lower to create clearance above for a multitude of manifold options.
To relocate the turbo lower here is a list of things I've already found that it would require (and surely there are things that would "spring up" I haven't yet discovered):
* clock turbo bearing section so oil feed is at top, drain at bottom (and hope that the old rusty bolts don't break!)
* fabricate, bend, or re-do oil supply and oil return lines.
* clock compressor outlet so that the outlet is pointing more towards back leaving adequate clearance for boost tube connection (also change lengths of wastegate supply hoses as needed.)
* re-do shift linkage so it doesn't interfere with compressor housing
* grind "ribs" off the top of the exhaust manifold so intake manifold fasteners are accessible.
* trim flanges of exhaust manifold with grinder to make room for the intake manifold flanges
* heat-shield between exhaust manifold and intake manifold (maybe use header-wrap, or custom-fab a sheetmetal one)
* adapt or fab new boost line for compressor outlet to intercooler inlet
* fab new 2.5" custom-shaped downpipe w/flex section from new turbine outlet location to existing exhaust system
* completely re-do the air intake system as it would need to be moved from the passenger's side to driver's. Find a spot for the air filter and secure it (fab brackets as required.) Add new hose or tubing between air filter and compressor inlet and from cold air location to air filter inlet. May need to relocate wires, heater hoses, etc to make room for the new location of the air inlet tract.
As you can see, there is no walk in the park here!
PS - my goal is to gain a power boost in my usable power range and/or broader the usable power range. I've read a lot about intake manifold design and studies up on it, but found that it's hard to very accurately predict what's going to happen and so at one point you've got to just try it on an actual engine and see! That said, my current power band starts at about the point where the turbo kicks in (which really starts at about 3500RPM when the turbo is in full sing, although I can lug it down to 3000RPM if I really need to) and it ranges up until the governor starts limiting fuel (5500+ RPM.)
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A good ported A1 intake would be hard pressed to outflow a stock A2 intake manifold....so I'd vote for the A2 manifold.
I don't think that's true, unless you are considering a digifant/G60 manifold. The digifant/G60 manifold has larger diameter ports than the standard A1 manifold (but from the outside, it looks pretty much the same AFAIK, IE: has same runner lengths.) The A2 gasser manifold that I've got and have shown in the pics above actually has runner diameters probably about the same diameter as the A1. I would probably port-match whatever manifold I end up using and might be able to get back into the runners several inches.
Looking at the RPM plots of the 1.8l GTI motors in my race class that are using the digifant/G60 manifolds, the power peak RPM seems a little bit high for ideal to me - at about 5250RPM. I'm thinking the longer runners of the A2 manifold might be useful if it added hp to my power curve a little bit lower than 5250RPM. I mean 5250 RPM is in my usable power band, but I'd love to get as much beef as possible under 5000RPM.
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(http://www.diesel-speed-shop.com/images/longintak.jpg)
what do you think about this? :D
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Those are some looong runners on that 5-cyl manifold there. Got a runner length measurement?
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I've been around... I suppose mostly lurking. ;)
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Those are some looong runners on that 5-cyl manifold there. Got a runner length measurement?
no but i can check it.
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Hey Jake,
I don't think you mentioned a support for the turbo downpipe.
Would you need an added support to take stress off the turbo/exhaust flange?
Maybe something like the NA diesel, dual downpipe support would work.
I was looking at an A2 NA diesel intake and the runners look like they could be longer than the gasser runners.
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Are the A2 NA diesel runners the same length as the A1s? I would assume VW left this design feature the same given the identical hp and torque specs of the A1 NA Diesel and A2 NA Diesel engines, however I have not confirmed this before by actually measuring and compating the runner lengths. I know they went to a plastic plenum / aluminum runner design on the A2 NA diesel manifold, while the A1 NA manifold is all one piece in aluminum up to the air filter.
I probably won't be taking on the turbo relocation project, at least not before next race season (which is, when the weather gets better and when I have more time.) I may reconsider a custom intake manifold fabrication project however instead. My brother may be on a track to becoming a professional welder (He is in army reserves training over the next 2.5 months, learning how to weld anyhow.) If he were to invest in a TIG setup after completing his training, he might be able to help me tackle such a custom fabrication project (tubular aluminum intake manifold) with ease. Although it would be sweet to get the turbo out of the way, it's just so much work, and the exhaust system has got to be pretty cloe to optimized already with the turbo in the stock location.
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(http://www.diesel-speed-shop.com/images/longintak.jpg)
what do you think about this? :D
lengh is about 46cm ( 18p)
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Thanks for the info.... 18 inches? wow! That should get you some low-RPM torque. ;)
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hey i know this is off topic, but by low rpm torque do you mean in the range of 1800 rpm?
I was wondering why a TDI gets full torque at around 1800 rpm while the IDI gets full torque at around 2500 rpm?
Is that something to do with the high compression, or the intake runner length/turbo size???
thanks!
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Not all mk1 intake created equal.
early mk1 have slightly bigger runners and smaller TB (but who cares about the TB)
Later mk1 and mk2 (cabriolet 90-93, G60 engine and all mk2) have the same runner configuration.
My opinion, there's way better.
Meet my 1.8 8v Turbo secret weapon. (mot mine pictured)
The Audi 5KTQ intake manifold
It's got bigger runners and better airflow
(Audi left, G60 right)
(http://img.photobucket.com/albums/v238/shipleyvw/IM000509.jpg)
Another interesting intake is the 2 piece Audi 90 intake (counterflow); it's got 4 injector holes in the intake for stuff like propane or nitrous.
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I was wondering why a TDI gets full torque at around 1800 rpm while the IDI gets full torque at around 2500 rpm?
I'd say its got more to do with the nature of direct injection combustion. Mixture formation tends to be best in DI engines at low RPM's, permitting a larger injected quantity without smoke. Mixture formation and burn speed is better at higher engine speeds in prechamber engines.
The early 1.9TDI uses the pretty close to the same turbo as the 1.9TD (both K03's) and both manifolds are very similar, pretty much logs. No tuned length runners on either one.
I like that manifold. It has me wondering if the transporter 2.4 5cyl NA diesel has D shaped ports like the 1.9TD. It has some seriously long runners...
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I like that manifold. It has me wondering if the transporter 2.4 5cyl NA diesel has D shaped ports like the 1.9TD. It has some seriously long runners...
no d shapped, i have to chek if it have same size as the 1.6 or bigger....
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hey i know this is off topic, but by low rpm torque do you mean in the range of 1800 rpm?
The 18" runner length might help add some torque that low in particular when compared to the stock 1.6lTD intake, but it's going to give it's greatest gains probably higher up, I'd imagine. I haven't done the calculations but I'm sure it wouldn't peak that low. I'm pretty sure you'd need something way longer that is practical to fit under your hood to give peak torque from intake runner inertia tuning at 1800 rpm. The air columns that long would also severely choke volumetric efficiency at high RPMs, since they require time (not available at higher RPMs) to get that long column of air movin'.
I was wondering why a TDI gets full torque at around 1800 rpm while the IDI gets full torque at around 2500 rpm?
Is that something to do with the high compression, or the intake runner length/turbo size???
It's not the compression, or the intake runner length. I think it's the turbo design. The TDIs have very small and quick-spooling non-variable or variable vane turbos that gives peak boost pressure at about 1900 RPM, while the 1.6lTD has a "bigger" turbo that doesn't kick in until a higher RPM. Regardless of which VW Diesel motor you're talking about, generally the torque peak occurs at the lowest RPM that the turbo can deliver full boost.
I'd imagine the 1.9lTD (coming with the small, quick-spooling turbo) would also peak at a low RPM when it's boost peaks, but I don't have hp/torque and boost pressure vs RPM plots for that motor handy, so I can't verify that.
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Jake, doesn't your GTD have a flat torque curve, with no real drop-off until you start running out of fuel?
Hint: Paste some dyno runs on your website and update that "Last updated in 1996 line... ;)
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thanks for the info! Seems like it takes forever for my turbo to spool up. Should I go with a 'dinky' K03, or would buying an expensive hybrid turbo be worth it? I don't want mean power, just less turbo lag :)
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Hint: Paste some dyno runs on your website and update that "Last updated in 1996 line... ;)
Couple of problems there:
1. I have no additional disk space on the web site
2. If I start modifying it, I know I would be tempted and it would be a very slippery slope of bringing it fully up to current, which would take a lot of my time that I don't have...
So I think I will just continue using imagestation, unless someone knows of a better option. Although it does tend to reduce the size of the pics, it works well with this board, and seems able to relentlessly store all the pics I can throw at it! ;)
Jake, doesn't your GTD have a flat torque curve, with no real drop-off until you start running out of fuel?
The torque peaks at the RPM where the wastegate opens, and either hold that amount, or drop, from there going on into higher RPMs. Horsepower, on the other hand, generally climbs up a little bit after the wastegate opening point, but is generally flatter than torque in this area. This characteristic is probably because the efficiency of the combustion drops off as the RPMs climb. Whether aero drag is being included in the measurement, or not, also does influence the shape of the curve recorded (as aero drag increases with increasing vehicle speed and RPM)
* Plot from G-tech, after aero drag, 3rd gear, not SAE corrected:
(http://www.imagestation.com/picture/sraid77/p57536b6dd032297329606ee82e2f4f6d/fb402251.jpg)
* Plot from a chassis dyno, at the wheels, SAE corrected:
(http://www.imagestation.com/picture/sraid158/p99757a67228beca937e81b4e81649d44/f51dc228.jpg)
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1.6lTD long runner intake manifold idea, take 2:
Instead of putting the long runners in the factory location behind the motor close to the firewall, another option is to make the runners go over the top of the cylinder head, like this:
(http://www.imagestation.com/picture/sraid192/pf2ea96386b2d9ff5cc90d30b0c862c9b/f1b6284e.jpg)
(http://www.imagestation.com/picture/sraid192/p02b051afd2a8bf6734e08f2a42615cc0/f1b6284f.jpg)
(http://www.imagestation.com/picture/sraid192/p7505acad50724e4c62fd8bdad5bb1243/f1b62850.jpg)
A test fit revealed I was able to close the hood down all the way and there was still a little bit of room. Although the throttle mouting flange clears the hood, I might want to cut it up to get a little clearance with the valve cover, and perhaps position the plenum down a little bit more.
To make service under the valve cover easy, the intake manifold should be a 2-piece design, with all the bolts for the upper piece being accessible without needing to remove the turbocharger. The upper piece could be an A1 gasser manifold that is stock except for a few unneded protrusions cut off, while the lower piece could be a special fabricated piece made from the bottom of an 1.6lTD intake manifold that allows the A1 gasser manifold to bolt up in the proper position. It would start with this piece:
(http://www.imagestation.com/picture/sraid104/peaf6e27a7a0e7184da90614ba4fd9857/f9957943.jpg)
Compared to the other long-runner intake manifold design, this would leave the exhaust manifold and exhaust system, turbo location, air intake and compressor outlet tubing, oil feed and oil drain, etc, all unchanged. The boost tube run from the front mounted intercooler would be shorter with less distance to travel to get to the plenum. The intake manifold also wouldn't be positioned over the hot turbocharger but in a location that's a little bit cooler, requiring less heat shielding.
As a con to this design, it uses the 1.6lTD intake manifold's tighter radius runner bend, which might restrict airflow somewhat versus a design putting the plenum behind the motor. I wonder if it that tight bend would make it much more restrictive.
Also due to more limited clearance, I wouldn't be able to easily substitute or test various types of long-runner manifolds (In particular, the A2 manifold, which has longer runners than the A1 manifold, would stick up too far and interfere with the hood.)
I have had trouble oxy-welding thin tubing (.065" tubing) but have had good results with thick (1/4"). But I need to see how well I can do cast aluminum. I'll need to do a little experimenting first to build my confidence. I suppose at worst case, I could always prep the parts for welding and take them to someone who can TIG things together.
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You deffinately don't want the crappy tight bend right before the ports style manifold, I know its like the factory manifold but that one sucks too. There is definately a big differnece in having the air going into your ports straight and cleanly and smoothly than making it make a 90 degree turn right before it goes into the cylinder. One idea I had while looking at some manifolds today was taking a a2 na intake and taking off the plastic airbox crap and buying a premade plenum and welding it on, I think it would make a really nice low cost long runner intake. The audi 5000 intake witha runner cut off is an awesome one too. I know you probably want to run the turbo in the stock postion and I would want to as well cause that would be a lot of work flipping everythign around. I am flowing huge amounts of air with a pd130 manifold on malones engine but it is a short runner and it has the d shaped ports.
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I tried some aluminum welding with the cast manifold material and although I can get good fusion sometimes, it's just not reliable and when it doesn't work, the oxides prevent things from sticking with my oxy-acetylene setup. I think I really would need an AC TIG setup to do the required work without becoming very frusterated. I do have a aluminum braizing rod I can use and is very strong, but it only works for gluing pieces together, not really good for the building up of material I'd want to do with the lower plenum.
So my latest idea is to fabricate a completely new lower part out of stainless steel tubing and either mild and stainless flanges. Stainless runners would help slow down the transfer of heat from the head and turbo into the main upper aluminum runners and plenum. I can very reliably weld stainless, and maybe use some thin-walled stainless mandrel tubing bends that have slightly more generous bend radii than the factory 1.6lTD manifold has. It's still going to be tighter than most stock manifold designs, but hopefully it won't give up a whole lot, it might be worth a shot! Flipping the turbo manifold upside down is just so much work, that it's unfeasiable for me at this time.
I did some more cutting, filing and deburring of the upper manifold piece that made it look prettier, and found cutting off a corner of the throttle body flange made it sit even closer to the valve cover. It is definitely looking workable!
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Flipping the manifold is definately a lot of work. I have an ac tig you are not too far from my shop so if you ever feel liek wandering north stop by and we could weld you up one that way. But until then I might be able to help you out with the flanges, my buddy is autocading out 1.6 intake flanges and 1.9 intake flanges and the exhaust flanges for both heads. He should be done early this week than I will mail the the drawings to my other friend with a cnc plasma cutter. So I can get them cut in aluminum, mild steel or stainless. Hey maybe we could trade some flanges for those new nozzles you are working on :twisted:
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Just out of curiosity I picked up a 1Y inlet manifold a while back, would that not be woth modifying to suit? either port the head and use a AAZ/TDI inlet manifold gasket or weld the manifold and port that to suit a 1.6l?
1Y is a european 1.9D, basically the non turbo version af a AAZ as I understand.
I picked up the manifold for my mechanical TDI when I get around to it...
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The nasty tight bend at the end might hurt flow more than any gain - I flowed a lot of intake manifolds on the bench, and it was surprising what worked and what didn't. Granted- this is just airflow and not inertia tuning.
Also, the steel intake manifolds on air cooleds that had Dual Kadron carbs eons ago had sealing issues. I am sure with a decent flange and good machining that wouldn't be an issure - just a heads up.
Haven't read this thread in a while, any 5-6 cyl VW/Audi/Volvo Diesel intakes that might work?
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Dave - thanks for your help suggestions. You have IM!
Greggearhead - I don't know of any other manifolds that employ long runners that would bolt on while clearing the high-mounted turbo.
The bend seems like a necessary evil of having the manifold clear the high-mounted turbo. Although I think it might look like more of a bend than it really is, because the airflow enters the head at a downwards angle. I measured the actual dimensions and bend radius of this bend a while ago... I need to find the notes.
Mr-Brick-Yard - How might the 1.9D (1Y) manifold be desirable? Got any pictures of one?
If there is some compelling reason to use a manifold that has "D" shaped runners, it is feasible. My racing class doesn't allow head porting, but it does allow gasket matching and the removal of material in the runners of the head up to 1" from the manifold bolting surface. So the runner shape could transition from a "D" shape to round shape up to 1" into the head.
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measurements of the 1.6lTD intake manifold lower bend:
The centerline bend radius is 1 5/8". It makes a 68 degree total bend. The angle of the runner as it enters the head is 22 degrees from horizontal. The inside diameter of the gasket-matched intake port is 1 3/16".
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>> (from page one by Blades) The Audi 5KTQ intake manifold. It's got bigger runners and better airflow
I've seen a number of people use that style intake in the gasser world. It's true that the manifold is indeed larger and has better runners and I had thought about using one on my 1.8 gasser race motor (FSP engine).
After doing some research and comparing the parts, I found that it would have required signifigant work to adapt this manifold correctly for use on the 8V head.
Other than chopping off the fifth runner, the ports on the 5ktq manifold would actually enter the head at a higher point than the stock manifold and at a slightly better angle. The Audi manifold, as a result, also does not extend fully to the bottom of the ports on the head.
From what I read, you'd have to remove quite a lot of material on the top of the ports on the head and possibly add some at the bottom. At least one person had concerns about the thickness of the "meat" of the head above the ports at the rear of the head...not sure about a diesel head.
Others have done it and reported good gains (supercharged gas engine) but that came with the disclaimer that it took quite a lot of time to finish.
In my class, that extensive head work is not permitted, so I'm going to go with a G60 manifold. It seemed to be a good compromise of runner width, shape and throttle body position. The A2 gasser digifant (last version of the 8V gasser) also seemed promising as well. Longer runners than the A1/G60/Fox intakes...
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The 1Y inlet manifold is this.
As the 5cylinder one pictured back there only it's 4 cylinder.
It has D shaped ports.
It's inlet pipe is a plastic flange with 4 bolts and different size adapters could simply be bolted on, they would have to be made in the first place though
I have one under the bench, did you lot not get those? 1.9 N/A ?
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Mr-brick-yard: thanks for the info, however it doesn't sound like it would clear the high-mounted turbo. :(
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Here's the latest with this project. I bought a big 1"x2" extruded chunk of aluminum and braized that to the lower 1.6lTD intake manifold runners that I chopped off from the plenum.
(http://www.imagestation.com/picture/sraid193/p8d7fd3a687dbf9021d69cb86e0283d82/f19ab28c.jpg)
(http://www.imagestation.com/picture/sraid193/peaa52b4185d2e2dade9005e8b20a8287/f19ab307.jpg)
The aluminum braize is really interesting stuff... it's very strong (tensile strength over 40kpsi), and it is also noticeably harder than aluminum. (You can definitely tell the difference when you hit it with a file. It's much harder to chew through!) It is very easy to apply with the oxy-acetylene torch, but because it's all runny liquid during application, you can't do as many things with it as you can with welding where you can build up material here and there, etc. But the braize has its uses.
The next step is to remove a bunch of material from the chunk to lighten it up a bit and also drill the ports out. I decided to braize the chunk first and machine it later so that I wouldn't have to worry about it being lined up perfectly during the braizing procedure. The flat surface also worked well to hold a puddle of the liquid braize on top of.
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I've made some progress on the custom 1.6lTD intake manifold project. I drilled and tapped all the holes for mounting the upper manifold piece to the lower piece. Using a drill press, I got the holes right on the money and perfectly parallel, so the bolts just dropped right in with no binding while assembling upper piece to lower piece. I was pleased with the way the plenum and manifold runners ended up sitting in their final position atop the junk head. :D I figure I'll probably have maybe a touch under 1" clearance between closest part of plenum and hood. I might have to do some clearancing in a couple areas to make everything fit, for example near the #1 runner I found it gets close with the turbo's compressor housing. It also might be a bit tight in one spot around the oil filler cap, but I'm not too worried about it.
With the upper and lower pieces bolted together, I scribed around the upper part where I wanted to remove the material from the 1"x2" aluminum slab.
Edit: here are the latest pics of the scribed surface.
(http://www.imagestation.com/picture/sraid193/p9916ed1f695d35c83b25e20fefa852fd/f187df8a.jpg)
(http://www.imagestation.com/picture/sraid193/p410725fe4b7ac4d5f18231683a05b44f/f187df7e.jpg)
You can see I have just started eating some material away using the drill press.
My plan is to eat a line of the material around the scribe line away, one drill press plunge at a time, and then "connect the dots" with a hacksaw or coping saw. Then I'll use hand files and die grinders to clean up the remaining rough edges. I also set the gasket on top of the aluminum slab and scribed inside the port openings; I'll also remove material inside the ports using the drill press.
Hey, if the ideal tools (like milling machines) were always available for these sorts of project, they wouldn't build as much character now would they? :wink:
I'm just happy to have access to a drill press and not have to hacksaw and handdrill all the way around that thick aluminum piece! :lol:
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Don't get me wrong, Jake, because I love playing with things...but did you ever try fitting a Mk1 GTI intake manifold?
(http://home.earthlink.net/~rps1976/Images/Diesel/IntakeEndView.jpg)
(http://home.earthlink.net/~rps1976/Images/Diesel/IntakeManifold-sm.jpg)
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Stan - The problem is that with the stock transverse-engine mounted 1.6lTD, with the high-mounted turbo, there is no room for any of the long runner intake manifolds to simply bolt up straight to the head. This pic helps illustrate the space restrictions:
(http://home.comcast.net/~vwgtd/icinstallside_3.jpg)
So the route I am taking is trying to make the long runner manifold fit by bolting it to a custom adapter that raises and rotates the long runner manifold. This allows me to leave the turbo mounting location as it is.
PS - that A1 GTI manifold looks exactly the same manifold as what I'm going to use! :) (Compare yours to the one in the pics from this post: http://www.vwdiesel.net/phpBB/viewtopic.php?t=614&start=27 )
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why not just flip the turbo and manifold upside down? seems like the exhaust manifold works rightside up or upside down, so it would be easier to flip the turbo and manifold and take youre car into a muffler shop to get a new exhaust out on, than it would be to spend weeks milling a intake manifold using a drill press?
better yet, just flip the turbo and manifold. put a 90 degree elbow on the turbo outlet and have that come up through a hole in the hood. it would look totally mad max.
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I think that has been discussed already and he has decided to go this way for now. All the additional work of flipping the turbo for an experiment might not be worth it.
I hope to mount my turbo lower so I can use a regular gasser manifold of some sort.
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better yet, just flip the turbo and manifold. put a 90 degree elbow on the turbo outlet and have that come up through a hole in the hood. it would look totally mad max.
You know you guys can have some pretty wacky ideas, but I love 'em! :wink: Unfortunately in my racing class, cutting a hole in the hood is not allowed, and the exhaust must terminate aft of the driver. Otherwise I might consider it! (I guess there is also the little problem that under heavy acceleration, the column of soot in front of the windshield might obstruct a clear view of the course! :lol:)
I actually am enjoying this aluminum fabrication project, as it's challenging for me and I'm learning new things working with the material. It is not my top priority, and so it might take a while, as I just work on it here and there. But so far I'm comfortably within my budget: expenditure for the aluminum block was like $16 and I already had the other parts. The time is good for doing the test fitting and manifold development while the head is already off the block. :)
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I was wondering, if you turned the exhaust manifold upside down (I know it's been discussed) but cut off the turbo flange and welded it the other way would it work?
The turbo would not be upside down and you'd have clearance for a long runner intake.
BTW nice work on your custom intake!
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better yet, just flip the turbo and manifold. put a 90 degree elbow on the turbo outlet and have that come up through a hole in the hood. it would look totally mad max.
You know you guys can have some pretty wacky ideas, but I love 'em! :wink: Unfortunately in my racing class, cutting a hole in the hood is not allowed, and the exhaust must terminate aft of the driver. Otherwise I might consider it!
We were working on our own mad max Rabbit. It has expanded metal for a grill and a big deer catcher on the front. It's also lifted. Unfortunately it sounds like it spun a bearing and it it's probably too much work to fix just for a mad max mobile so we can run over stuff. K cars are $200 and work fine for running over stuff.....We were going to weld up a basket for the top and put the spare and some cans of diesel up there. :D
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I was wondering, if you turned the exhaust manifold upside down (I know it's been discussed) but cut off the turbo flange and welded it the other way would it work?
Cutting thick high-nickel cast iron/stainless of the turbo exhaust manifold and re-welding it while maintaining good airflow and strength could be very difficult. But it could be feasible to fabricate a simple steel or stainless adapter to rotate the turbo by 180 degrees. I can see some advantages potentially when combined with flipping over exhaust manifold, as it would leave the air filter location alone, and more of the air intake and boost tubes and air tubes could be adapted or re-used than if the exhaust manifold were flipped with turbo bolted to it as it originally is.
Although this is a good new idea, I'm going to continue down the custom intake manifold route.
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On my intake manifold design, I estimate the runner length of the manifold runners will be roughly 12" (9" runner of the A1 manifold, plus approx 3" additional the extension/adapter.) Adding in the 4" intake runner length that's in the head makes a net runner length of 16".
Simulating this in a spreadsheet I made that calculates various things, the Chrsyler formula predicts torque will be boosted in the range of 4400-6450 RPM, and most significantly at 5250 RPM.
The organ pipe formula predicts 4 torque-boosting reflective values would be put into my working range: the 3rd RV (at 6200 RPM), 4th RV (at 4650 RPM), 5th RV (3700 RPM), and 6th RV (3100 RPM).
All of the RPMs calculated assume a constant 104 deg. F air intake temp. Doing a sensitivity analysis of how much the boosted RPMs vary as a result of changing air intake temps (which result from changes in ambient air temps as well as imperfect intercooling under boost pressure), the boosted RPMs rose 200-300RPMs when increasing the manifold air temps from 86 degrees F to 140 degrees F.
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Although this is a good new idea, I'm going to continue down the custom intake manifold route.
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I wasn't trying to discourage you in anyway. I wanted to know if it was a possible solution. For someone without the tools and skills to tackle the custom manifold route, it's a good solution. By doing it yourself you're sure of ending up with the results you wanted.
Nice work man!
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Update:
The drill pressing is now done. Although it needs a lot of filing and die grinding to clean up, you can now make out the manifold's basic shape:
(http://www.imagestation.com/picture/sraid194/p31b25f88588b5658613da96e7e13d039/f17829af.jpg)
(http://www.imagestation.com/picture/sraid194/p4e353e3ba3a2895070a2ce0ca265577b/f1782ba5.jpg)
I also used the drill press to punch the runners out to 3/4" initially. I might try using a die grinder to take them out the rest of the way and make their final intended curved shape.
(http://www.imagestation.com/picture/sraid194/p6369bf596effd8999ad912b3b40b298e/f1782eee.jpg)
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thats looking real good there.
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Nice work. This thing is going to be quite impressive when done!
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Thanks guys! I did some hand filing and die grinding on the intake adapter piece and it's really coming along. I've still got a ways to go on hogging out the ports, but the carbide burr is definitely the right tool for this job.
I also tried out some new flux-core welding rod I got today and I really like the stuff. On my first try using it I welded two cast aluminum intake manifold scrap pieces together with great fusion.
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Way to go. Sounds like you are getting a good handle on Al. welding, cast is the worst Al. to weld, if you can weld it you can weld pretty much anything.
Remember when welding Al. "cleanlieness is next to godliness" esspitaily old cast Al. as cast is quite pourous it tends to pick up anything around it contaminating it and making it a bugger to weld, when I weld anything old and cast I spend a ton of time first wire brushing it then using a good chemical cleaner, then back to somemore wirebrushing, and the an oxideremovingacid to help reomve the oxide just b4 welding. Then with a TIG with balance contorol I move way more to cleaning, and turn the heat up some. I know that you are using oxyacetlene to weld, so I would do all of the above, and then use the flux paste you have as well as the flux-cored rods, and you should get through the worst of the worst. Post up some pics of the welds. :D
My spelling is terrible tonight :oops:
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Jake,
I've been reading this thread with interest because I'm trying to fit an A2 long runner manifold onto the Quantum engine in my TurboTub :D
I'm using a VNT15, and as I think you found with your Dad's Rabbit, there is an interferance problem with the EGR (and/or wastegate) flange. I have cut one of the threaded bosses off the bottom of the manifold, and now I'm real close to clearing, but still not quite there.
What I'm considering now is to space out the exhaust manifold/turbo from the head maybe 1/4", as I think that will give me the clearance I need. I'm thinking I could either cut 1/4" copper plate spacers with my plasma cutter, or get an old exhaust manifold, cut off the flanges and have them surface ground to make them square and flat. Of course I'd need to fit longer studs in the head either way.
Which do you think would be best from a structural/sealing standpoint?
moT
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DVST8R: Thanks for the tips. I was actually shocked how well the flux-core rod worked, which tells me a lot of my previous problems must have been caused by inadequate and/or inconsistent fluxing. This rod is amazing... on that first test I mentioned, I only prepped one area very lightly and quickly by hand scrubbing the oxides off the surface with a brush and I left another area totally original, old cast oxidized. I did apply some supplemental flux across the whole surface I was welding on for good measure. The prepped area definitely welded a lot better, and prepping it more could only have helped. But I was shocked I was even able to weld the completely unprepped area together! Wasn't that easy, but I found like welding stainless, I was able to "scratch" the surface to help get the the metals to flow and join. I will definitely spend a lot more time prepping on any real welding project I do, this was just an experiment to see how the new rod worked. Getting good fusion was so much easier with the right amount of flux being where it needs to be. When I built up some filler material on the surface, I no longer had problems getting it to "sink in" and flow out.
My latest aluminum welding problem is that sometimes when the flux gets thick right where I'm welding, it glows so brightly I can't tell where the molten puddle is! On my test this only happened once when I ran a bead towards another area I already welded, but I had to stop when it happened. They make special welding lenses to block out this "sodium flare", which is I think may be the last piece of new equipment I'll need before being ready to tackle the real projects.
Oh, my test piece of aluminum, the weld really isn't too pretty. Heat management is really tricky with this stuff, so I didn't run the prettiest bead. It turned out to be a much more difficult weld than I planned because it was one small thin piece joining to a thick piece. I didn't melt through anywhere though (right at the beginning, I was very close though!) I'll practice up a little more. :)
PS - I might have to try those chemical cleaners you mentioned.
moTthediesel: VNT-15 and a long-runner intake... :shock: going for a little bit of torque, eh? :)
I was able to get an unmodified A2 manifold to fit the VNT-15, no manifold spacer required. Pics are in the VNT 1.6 diesel thread. I removed one of the studs from the EGR flange and replaced it with a countersunk allenhead cap screw that I rounded the shoulder partially off of to make additional clearance, but it all fit bolted up with the VNT-15 and the unmodified A2 manifold to a 1.6 liter head. A specially contoured EGR block off plate (which I made in stainless) was a key ingredient. Even made an intake manifold support brace. I didn't end up using any of it. I held on to the pieces and they aren't doing much sitting in my garage. You don't want to know how many hours I have into them. If you could use them for your project (also could part with the A2 intake, which you might want since it's been tested to fit, and also has the mounting flange to bolt up the brace), send me an IM.
Also, although I never tried test fitting an A1 intake manifold to a VNT-15, it might fit easier than the A2 so might be worth considering. It's got shorter runners though.
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Jake... looks great so far! I'm really interested to see how the intake affects your engine's powerband. Will you be using your G-tech again to do the same sort of testing? I'm assuming you have the plots from before the work began.
>>I also used the drill press to punch the runners out to 3/4" initially. I might try using a die grinder to take them out the rest of the way and make their final intended curved shape.
What type of stone/material do you like to use? I've been experimenting with the ports on a manifold and the gray stone I'm using gets very clogged pretty quickly when I'm using the die grinder.
It's frustrating because I can only grind for a minute or two, then I have to find a way to scrape off the Al that cakes the stone. I tried using my wirewheel / grinder, but that erodes the stone and only works to a point... What's the key when working with aluminum?
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the gray stone I'm using gets very clogged pretty quickly when I'm using the die grinder.
A stone bit (like the grinding wheel material) works OK on ferrous metals, but like you've found it's not the correct tool for aluminum, because it will get loaded up in a hurry. For similar reasons you can't use a grinding wheel on aluminum or a metal-cutoff wheel on aluminum.
For removing lots of material, a carbide burr also known as a rotary file (a good source of these is on ebay, from "naburs") will eat through that aluminum like you wouldn't belive, especially if it's got the course threads per inch style with the long continuous flutes (no cross-cuts), which is specifically made for "fast cutting" aluminum. Beeswax in the cutter fillets will help any type of carbide burr or other cutter (including a drillbit) keep the aluminum from sticking to it. The course-cut burr, especially if it's a smaller diameter, will leave kind of a rough texture though, and may also be hard to control as the teeth catch on the material it will try and jump around and "dance"... (so, use both hands spaced far apart on the die grinder and short style burr) also for ports it needs to be finished off afterwards with something that uses sandpaper grit, like a flap wheel (comforms to surfaces well), or a cartridge roll (doesn't conform well, but are cheaper and cut material quicker I think). Flapper wheels (which is simply a 1/4" shaft with a slot cut in the end with a strip of emery cloth stuck through it and rolled around it) are another option some use for final finishing, but I haven't tried them. The course-grit cartridge rolls can hog out the aluminum effectively as well, and are smoother and so easier to control than a rotary burr and get a good finish on. Tip for when you're working on ports: to get the perfect good "shape" more effortlessly, try and find a tool with a larger diameter (but small enough to fit comfortably inside).
My engine builder just uses cartridge rolls for port gasket matching and the results look great. He starts with rough grit then switches to fine for finish. I'm planning to buy some myself, I just got a mandrel, now just need to find a supply of the rolls.
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Heh, I found that out too when grinding out my intake on my 8v gasser to fit the Audi 5000 Throttle Body. Had to use a lot of lube and keep the speed slow. Took a LONG time! I had a nice porting kit from Standard Abrasives, I used it to port/polish my iron heads for my Camaro (that I never got around to installing) and the stone bits worked really well for the iron- and the flap-wheels worked really well for smoothing out the ports and making a nice final finish on everything. I found I could get the combustion chambers polished to a mirror shine with the "cross-buffs", they are a sponge-like bit with abrasive medium on the "crosses". Kinda hard to explain, but the instructions that came with the kit said to use a little wd-40 to keep the medium clean, so I did and I was really impressed. The kit I used was the "deluxe porting kit" http://store.summitracing.com/egnsearch.asp?Ntt=porting+kit&N=115+301466&D=301466&Ntk=KeywordSearch
and it comes with a lot of cartridge rolls. They arent the best quality rolls but the kit comes with so many I had more than enough to do 2 V-6 iron heads with plenty left over. The rest of the components are decent quality though, but they didnt come with any carbide bits. Oh well. :)
It was a good learning experience anyway. :)
Brendan
84 Scirocco 8v
00 Camaro L36 M49
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Well...this looks sorta familar. I've provided some pics of my IDI TD setup when I had just finished rebuilding it and also added my own "plenum style" intake manifold to the bunch. It was crude, but was effective using the 1.8 JH Rabbit GTI intake manifold which I then port matched to the head as well as port matching the head. I also grinding the portion off the rear of the intake manifold that allowed it to attach to the gassers exhaust manifold for added strength. Thing is...the setup wouldn't allow for the stock TD style exhaust manifold which has already been outlined here and we went the route of a custom log style, center/back mounted exhaust manifold to complete the system. It did help...never did dyno it for "exact" power increasing but with the fueling modications and 25psi + the propane system I had made I did notice some benefits to the setup. Flow I believe was improved as well as transfer of the charge cooled air ...the feeling is "smooth" I noticed that my highway "boost" was down about 2psi after the intake manifold switch as well as the EGT's by about 100 degrees. Power wise...eh...didn't notice much. I'll be running a similar setup on the TDI. Very nice job so far though Jake...here are some pics of what i did...rough stuff, and now with all this talk i kinda miss the IDI TD i had sometimes :( luckily to have the 79 now...not TD, but reminsant non the less... :)
Roughing and mocking right after I port matched
(http://i18.photobucket.com/albums/b109/joeallison_99/IDI%20TD%20BYE/000_0049.jpg)
Detail
(http://i18.photobucket.com/albums/b109/joeallison_99/IDI%20TD%20BYE/000_0050.jpg)
The combination thanks to greasecar on the exhaust manifold
(http://i18.photobucket.com/albums/b109/joeallison_99/IDI%20TD%20BYE/000_0051.jpg)
Finished product
(http://i18.photobucket.com/albums/b109/joeallison_99/IDI%20TD%20BYE/000_0118.jpg)
Installed with the rebuilt motor...
(http://i18.photobucket.com/albums/b109/joeallison_99/IDI%20TD%20BYE/000_0121.jpg)
The ugliest part of the whole deal....the "intake flange" i crafted to work in place of where the TB used to be. This time around I'm modifying the boost return section of a G60 throttle body to accomodate my needs on the m-TDI
Have lots of pics around of the old setup if anyone is interested...including the intake manifold, etc... I like the idea of what your doing though...long runner...and utlizing the old style manifold...very cool.
Joe
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Hey Joe I remember that exhaust manifold made by greasecar Justin in the early days of the forum... didn't realize or remember that you coupled it with a long-runner manifold though. Nice work. Did you aluminum weld the EGR and cold start bung? Looks interesting. Cutting / fileing / grinding that EGR piping off the back of my A1 manifold was a lot of work but I got it off of there (still need the plug the hole on the plenum from it though, but that's why I'm practicing my aluminum welding :) ).
When I'm done with this and have the Rabbit back up and running, I am definitely planning on scientifically testing the performance impact, will use an RPM-sensing G-tech. I'm in a competitive racing class, and I want to know if power is hurt anywhere in the RPM band, or helped anywhere, and by how much compared to a stock 1.6lTD manifold. I will for sure need to take a new baseline test with the stock 1.6lTD manifold, since many other variables have changed since my last G-tech testing and all I want to test is the difference the manifold makes.
I had some success today in finding tools needed to complete this project. I found when running my air compressor cycling it on and off often, I noticed the cylinder head temps get kind of hot (too hot to touch). Well to help that situation I picked up from boeing surplus a $5 special electric fan and mounted that to my air compressors air shroud, set it up to blow air into the shroud to help out the crappy internal fan keep the compressor cool. I can leave the electric fan on all the time so it will help the compressor cool down even in between cycles. The electric fan works great!
I also found a local source of cartridge rolls and bought an array of them, and have just started experimenting with those... the carbide burrs definitely hog out aluminum quicker than even the coursest cartridge roll I tried (60 grit). My local engine builder uses 60 grit cartridge rolls for the rough port cutting and 80 grit for finishing so I got both of those grits. I also picked up some 120 grit to give polishing with it a try. The cartridge rolls leave a nice smooth finish that is way better looking than the carbide burr marks.
The abraisve supply store I went too had the cross-buffs (about $3 a piece in the 1" diameter) and I almost bought some to try out, but they didn't have any mandrels to go with them so I won't try them this time. They looked pretty interesting though. Probably handy for final polishing odd shapes. So anyway, I've got plenty of air tool toys to play around with now... :P
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Jake,
Yeah, I think at the time it was summer which I found myself finishing the car up and also out on the road more instead of in on the forums. Though...building, we were here all the time it seemed...advice, suggestions, etc.
Yeap, thats Justins manifold. I let it go with the TD motor...probably shouldn't have but the guy that bought the motor thought that he could use it possibly sometime plus I went with a different design PSI cast ''back side" manifold for the TDI. I think velocity will be better with this setup. Plus, i was restricted to the keystone flange for the turbo on the homemade manifold. Short of building a new collector for it and using a standard T3 flange I would have had to use a stock turbo.
As far as the intake manifold. I had that on pretty quick that winter of the build. It took alot of grinding with a bigger grinder and pneumatics and then filling in the extra holes via a friend that could aluminum weld... he is the one that also helped me build the air/water intercooler I'm using for the TDI. The only skill I still don't have that I'd like to is the ability/resources to weld on my own. At home I have a 80gal compressor, all the tools for it... but only a torch and an ARC welder... that'll change soon. Looking into my own MIG setup to learn on.
So... i think thats it. Maybe more later...gotta go to work now :)
Joe
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Intake manifold fabrication update:
Did some SERIOUS die grinding... spewing aluiminum shavings everywhere. Sharp little guys that can stick in your clothes too! :o Did a lot of "hogging open" in the ports. The outside shape is also almost done now. Looks nice after being finished with a cartridge roll. Not even close to done with the ports yet though.
One problem I have is the angle of the runners as they flow from the top piece to the adapter piece is at an angle of 22 degrees. To avoid an overly abrupt turn, I want to add some material to the upper piece's runners so they start turning higher up so it will be a more gradual radius of a transition. I'm consider welding to the aluminum just on the inside of the flange to build up material here, but I have a vision of horror of the runner flange melting through while doing this and falling away. Maybe if I heat, add some filler, and let it cool, then repeat, I could build up material that way. Those welding glasses shielding out the sodium flare sure would be nice.
I also test fitted the intake manifold to a cylinder head with K24 turbo installed, and verified an interference problem with the K24 turbo compressor housing. After about 1/8" of clearancing on the outside of the #1 runner at the flange where upper piece joins lower piece, it looks like I can fix it with a 1/8" shim on the turbo mounting flange, which if I made out of copper would work like a gasket so that's my plan. I just hope the Garrett turbo fits.
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Keep up the good work. This makes me happy I will likely be mounting my turbo lower.
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Pic update...
Turbocharger gasket / spacer, fabricated out of 1/8" copper:
(http://www.imagestation.com/picture/sraid194/pab54441f29db595c596860b2ec3332b4/f1665212.jpg)
Intake manifold adapter piece progress (rough-cutting is almost done)
(http://www.imagestation.com/picture/sraid194/p4d8c5f7e7e543b69956ee47d2044bfe8/f166521d.jpg)
(http://www.imagestation.com/picture/sraid194/p7ce937d80617dcc67dd7e6873d4b388b/f1664317.jpg)
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Air die grinding tools doing most of the work, from left to right: grinding stones, die grinder (with cartridge roll mounted on long mandrel), large cross-cut carbide burr (for steel), 2 small aluminum cutting carbide burrs, 2 short cartridge roll mandrels (one with cartridge roll mounted), small cross-cut carbide burr for steel, 2 flap wheels.
(http://www.imagestation.com/picture/sraid194/p5e5bd9a9a1731310d0042c9c4830b816/f1664d6d.jpg)
My recently acquired air compressor, providing the grunt labor for all the cutting and shaping, after being modified with an added 32 watt cooling fan (in rear, at left in pic) and aluminum sheet shrouding (visible in front) to direct needed cooling air to the cylinder head for hours of flat-out metal shaping fun. :twisted:
(http://www.imagestation.com/picture/sraid194/p9ab7f34747e59d9354724e10de3a139a/f1665248.jpg)
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Jake this is awesome, I love watching your work :)
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Dvst8r asked to post up some pics of my oxy-acetylene aluminum welding, so here you guys go...
This is a really big hole that needed to be plugged. It was where the EGR piping (which is now cut off and ground away) entered into the plenum. I opened it up until the wall thickness around the hole was uniform and made a "keystone" shaped cross-section so I could make a plug that fit securely without falling through:
(http://www.imagestation.com/picture/sraid195/pb626526d794b2d195bc6743a50514e47/f15bd2d2.jpg)
Here is the plug fabricated out of 1/4" 6061 (and the tighter the fit-up, the better):
(http://www.imagestation.com/picture/sraid195/p017a0232ac341cf59a1b65fcbce6330e/f15c2d87.jpg)
The area pictured above just welded (flux resides also washed off with hot water and soap):
(http://www.imagestation.com/picture/sraid195/pd8ceacd426b1460949cd5453b1c3aa46/f15bd391.jpg)
... and now after grinding the beads down flush we can see how good the fusion really is. What a successful weld will look like here is uniform metal. This looks pretty good, but there is one area in the upper-right of the weld bead where a telltale thin line of non-shiny oxides shows that the molten metal didn't flow together correctly:
(http://www.imagestation.com/picture/sraid195/p419d2492634f018aa5211044d4a0015d/f15bd440.jpg)
There are a couple little holes (originally brake booster vacuum line and valve cover crankcase vent return lines on the gasser application) that I wanted to plug so I started by fabricating tight fitting plugs and hammering them snugly in:
(http://www.imagestation.com/picture/sraid195/p73ded99dc2eea524ea4897cc4ab5336d/f15c2424.jpg)
then, the view after welding:
(http://www.imagestation.com/picture/sraid195/pa3caf3f95238ab5961c88eb7f82535b2/f15c2b76.jpg)
And after being ground down:
(http://www.imagestation.com/picture/sraid195/p5152804b90c84584be923c1d49fc9d5c/f15c29ef.jpg)
The weld beads on both of these plugs had perfect fusion all the way around on both! :P I think the reason they came out so well was I had my flame set very hot when doing them.
But another area I tried welding (an attempt at repairing a previously botched weld) didn't come out quite so well. I didn't use enough heat so didn't get good fusion. I might have to try re-welding it... again. :roll:
Previous botched weld ground out ready for repair attempt:
(http://www.imagestation.com/picture/sraid195/p46bf0e8bdcbb4eab96ed670dd523d2c8/f15c2604.jpg)
After welding repair attempt - before cleaning off flux and oxide residue:
(http://www.imagestation.com/picture/sraid195/p91d20207a2158bd591341576ff9143bf/f15c2bf1.jpg)
After cleaning off flux (just soap and water):
(http://www.imagestation.com/picture/sraid195/p182bbb9cb487974445d2cc7a38e3f0d6/f15c26b8.jpg)
And after being ground down flush. Yikes, this doesn't look much better than it started. The metal has many areas that didn't get fused together. This is because I didn't use a hot enough flame.
(http://www.imagestation.com/picture/sraid195/pf2dbc541e8980477baf4e908f45ec5d7/f15c2538.jpg)
This has been good practice, so I feel more prepared for taking on the more challenging aluminum welding jobs needed elsewhere on the manifold. :P
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Jake, just to give you an idea of "how" i'm refining my manifold idea this time around with the TDI vs. the plenum style I had before...here is what I'm working on...may help with your project too as far as an inlet piece and "what" i decided to use....
I'm going to be using the G60 manifold. The ports need ported out rather heavily to match the D ports of the TDI, but I believe there is enough material...i'm going to work on marking it tomorrow.
Here is the manifold fresh and clean :) ready to mark and port
(http://i18.photobucket.com/albums/b109/joeallison_99/TDI%20ENGINE/100_1925.jpg)
However, the inlet piece is a bit more interesting. The one problem i had before was getting the very "crude" inlet flange I had made for the GTI manifold was getting it to seal well. This time around I thought about my experiences with the Corrado G60, then Lysholm I had and built. I remembered that the throttle body consisted of two parts. the TB itself and a section that bolted to it that was for boost return from the supercharger. With a little modification this is going to work well IMO. I don't have a pic up tonight of what it looked like prior...but you'll get the idea when you see this...
The piece
(http://i18.photobucket.com/albums/b109/joeallison_99/TDI%20ENGINE/100_1926.jpg)
Here is a shot of the bottom where I cut off and removed the butterfly valve for the boost return. I'll only need to have a cap welded over this hole after I smooth it out and its finished...
(http://i18.photobucket.com/albums/b109/joeallison_99/TDI%20ENGINE/100_1927.jpg)
Fitted to the manifold....
(http://i18.photobucket.com/albums/b109/joeallison_99/TDI%20ENGINE/100_1928.jpg)
How is yours coming along?
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Hey Joe - nice G60 boost tube adapter piece! What is the inside and outside diameter of that boost tube connection? It looks very good and I'd be all over finding one just like it to use on my project if my plenum weren't so tight against my valve cover. But since mine was so tight to the valve cover (I had to hack off a corner of the throttle body flange, including a bolt hole, to get it to fit), I will be doing something necessarily more tricky. I will weld material inside the opening at one area to build up the sealing surface and also will tap a new bolt hole. I'm also planning on re-using 2 of the original throttle body bolt holes, for a triangular shaped bolting pattern. To make the boost tube adapter piece, I'm planning on using an aluminum boost tube piece I got from a Saab which has close to exact the same diameter as my current boost tubes (about 1 7/8" OD). I will cut the beaded end off and weld it to an aluminum plate and bolt that to the plenum. I decided that the boost tube will be off center from the old throttle body opening to position it better. To achieve this, I hacked out some of the throttle plate sealing surface and even some of the plenum wall. :shock: (I'll build back up new plenum wall spaced farther away by welding on some aluminum plate.)
I've also cut off the v-band blow off valve flange from my scrap pieces of old 1.6lTD intake manifold plenum, and will be welding that to my new manifold's plenum wall just around the corner from the bolted on boost tube connection. I test fitted everything in the engine compartment first, which I'm glad I did, because the original blow off valve position I had in mind farther away from the throttle bolting surface would have been in the way of the LDA. The newly planned place I have for it has comfortable clearance.
I also took a close look at the planned boost tube routing from the intercooler to planned plenum connection, and it is looking great... much shorter than my old boost tube setup. There is a long section of my old boost tube, probably about a couple feet that I won't use at all with the new intake manifold, and I might not have to modify the boost tube that couples compressor outlet to intercooler inlet at all! :D
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I did some successful welding last weekend, repairing almost perfectly the previously botched welds. After being ground down, you can't even tell it was ever welded in the first place... :) I am learning how important it is to vary the heat when welding aluminum, and the heat this big manifold needs to get up to welding temperature at first is tremendous... but using essentially all the heat I can muster from my torch setup cuts my pre-heating time and gas usage considerably. Of course then there is the problem of having to dial the heat down after welding starts, to keep the molten puddle from growing too large.
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Jake, the ID on the G60 boost return section of the throttle body is 2.25 in. and the OD on that same inlet side is 2.5in . The portion of the plate that mounts to the manifold itself uses the same port design and gasket that a standard 8v throttle body uses... very nice...should flow very nice :) Let me know if you want more detail pics or something...there are a few up for sale on the vortex... Just post looking for a "G60 boost return valve off the throttle body" :)
Joe
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Plenum work update pics from today...
here is the plenum cut out to reconfigure the throttle inlet plate for the boost tube inlet:
(http://www.imagestation.com/picture/sraid195/pdf22db6effd271e0282122ad9f6aec2f/f13c263d.jpg)
I cut pieces away squarely, so I could weld in tight-fitting pieces of 1/4" plate.
Here is the first piece of plate set in place, all prepped and ready for welding:
(http://www.imagestation.com/picture/sraid195/pa8149612d6fa2be113eb5662035caf9f/f13c2598.jpg)
The round hole by the way is where I'll be put the blow off valve.
Here is welding progress with the first and second pieces successfully welded:
(http://www.imagestation.com/picture/sraid195/p74a6fb0e1aad9ec8cb84f8fde262ab31/f13c24f1.jpg)
Now there's a third piece welded on on top of the second to build up the flange area:
(http://www.imagestation.com/picture/sraid195/pd098eca856cda9ba505c93dbd4a5be5a/f13c1eea.jpg)
Here is how the built-up flange area looks with the boost tube coupling held where I want it to be located. I know the location seems kind of random just from looking at this picture, but when I get it done and mounted in the engine compartment, you will see why I chose this position.
(http://www.imagestation.com/picture/sraid195/pe7ac1e0abc97ea8428b64f2b20d6cd25/f13c22af.jpg)
And here's what the flange looks like without the boost tube coupler:
(http://www.imagestation.com/picture/sraid195/pf73b46aab60fcbd10789ab8e6c2531db/f13c2451.jpg)
I've still got to weld in some more plate to build up the flange some more, and then I'll file it flat and make a boost tube coupler piece that will bolt on. Very much a work in progress... :o
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I did some more fileing and shaping on the plenum. I made a plate (pictured below), which I'll weld into the plenum opening to partially close it off. I'll re-cut a new hole in an offset position so the boost tube inlet won't be so tight against the valve cover.
(http://www.imagestation.com/picture/sraid195/pb0967a92d178869745fbb14156075297/f136b068.jpg)
Hopefully all this plenum fabrication work will end up making sense when I'm done. :shock:
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Makes perfect sence to me. Now as long as it still makes sence to you, your set. :P
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Well, it makes a little more sense now. The design is definitely evolving a bit as it's being built. :oops: The blow off valve flange is now welded onto the plenum, the the air inlet flange is just about done.
When I first tried welding the BOV flange to the plenum, I tried my usual procedure of just going at the massive aluminum piece with a very large tip with very hot flame setting. Well, this caused problems with the lightweight blow off valve flange coming up to melting temps much quicker than the relatively massive intake manifold piece which conducted heat away from the weld area. Despite doing my best to direct the temperature of the flame to the manifold, the heat control was very poor, and I melted away some areas of the BOV flange - some where the v-band clamp touches, and one melt through was so bad even part of the critical o-ring sealing surface fell away! :shock: By the time that happened, I knew what I was doing just wasn't working, and so I stopped before the damage became irreversable. I then came up with a new strategy: I would try pre-heating the manifold to 400 degrees F in an oven, then see if the larger piece would melt easier. I used a smaller flame and less heat. The pre-heating method worked so well, I manage to pull off a perfect 360 degree weld that perfectly fused and sealed the inside diameter of the blow valve to the plenum! :) The molten puddle was much easier to control. I'll have to remember to pre-heat more often when welding dissimilar metal thicknesses. I also successfully built up a weld bead to replace the areas that had fallen away. I'll have to shape them carefully with a file to restore the original surfaces.
The air inlet flange is coming along nicely. With a hole saw, I made about a 2" hole in the face of the air inlet flange. I'll enlarge that to at least the ID of the 2.25" boost tube to allow me to move one step up from 2" boost tube size if I wanted, and the larger hole will also give me better access to inspect and clean out the inside of the plenum. To accomodate the larger hole size, I am leaning towards using a 4-bolt (trapezoidally shaped) sealing flange instead of a 3-bolt / triangular shape. The material where I'll need to drill and tap one of the bolts is a little thin walled and I might only get about 1/4" of threaded meat though - worst case scenario is to add more threaded area, I'll need to cut the section away and replace it with a thick aluminum chunk in its place.
I am trying to figure out what to do with the boost tubing. Here's what the old configuration of the engine bay and boost tubing looks like:
(http://www.imagestation.com/picture/sraid114/pfaf975d1f184d87477d0fb04dd63f80b/f8d3edbb.jpg)
The intercooler outlet diameter is 2.25", and the old configuration of boost tubing has the air go through a crappy nonreinforced rubber 90 degree hose (would really like to get rid of this) before transitioning down to a 2" tubing size. Even though I found the intercooler and boost tubes weren't highly restrictive after installing them as measured by my boost gauge, I'm thinking a little airflow optimization here might be worth my while. Not sure yet if I'll stick with 2" OD boost tubing to the intake manifold, or step it up to 2.25" OD.
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Looks like a lot of work hopefully it all pays off :) When I do intercooler fabbing I make the piece from the compressor to intercooler 1 piece and the piece fromt he intercooler to the intake 1 piece. Always, which sometimes means I fab up some pretty crazy looking snakes but I think it is worth it for optimal flow. Also why not try a cross flow IC? I am in the middle of fabbing the charge piping for a 16vturbo in a rabbit right now and we ordered this great cross flow IC that fits in front of the rad. I'll see if I can get some pics up soon.
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All an intercooler can hope to do is cool the intake air to nearly ambient temp while giving nearly zero pressure drop. Based on tests done with my current intercooler (Audi5000) at pressures up to 14.5 psi being tested, there is just too little room for improvement left on the table to warrant any changes. The intercooler was already 85% efficient at cooling the charge and had less than half a psi pressure drop.
However, I will continue to monitor its performance at the higher boost pressures I plan to run at, as it will get more heat thrown at it it will need to cool, it is likely that it won't keep up quite as well. I've added good baffling and radiator fan pulling air through it I will let run in grid to keep it cool though :twisted:
I am a little concerned about how much boost pressure the plastic end tanks are OK at, but I am looking into adding some reinforcements. Just got a lot of other things to do to prepared for 2006 racing season, and time is ticking away.
I'm always interested in seeing other Rabbit intercooler installs, and would be even more interested in hearing about other intercooler test results.
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(http://img393.imageshack.us/img393/4038/1129908938a49451wk.jpg)
what did you think about this setup?
(http://img393.imageshack.us/img393/8503/1129910804a68737vy.jpg)
(http://img393.imageshack.us/img393/8794/1129910763a55803hn.jpg)
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That's from the almighty Zonker right?? This intercooler setup is really cool and functionnal.
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i think theres a scoop, just that its mostly out of the picture. see the black thing on the hood in the second picture? i think thats the firewall end of the scoop?
thats really nice, btw.
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It sure does looks like the screaming yellow zonker (http://europartsinc.com/zonker/history.htm). That is an eye-catching intercooler for sure, you don't see top mounts on VWs too often, reminds me of the current Subaru intercooler setups. Kind of funny though how the Subaru guys like to ditch them and go front-mount. I think top mounts have problems with heat soak from the engine underneath when the car is sitting still. You'd need to run a cooling fan or always keep the car moving to keep airflow moving downwards through it and not convecting hot air up from the engine. Pretty neat install on the 16v intake manifold they way they did it, except it looks like it could use some baffling between the hood and intercooler to get more airflow from through the intercooler core and less escaping around its edges.
Here's a pic of the scoop I found for Andrew:
(http://europartsinc.com/zonker/images/scoop_sm.jpg)
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Well, it makes a little more sense now. The design is definitely evolving a bit as it's being built. :oops: The blow off valve flange is now welded onto the plenum, the the air inlet flange is just about done.
When I first tried welding the BOV flange to the plenum, I tried my usual procedure of just going at the massive aluminum piece with a very large tip with very hot flame setting. Well, this caused problems with the lightweight blow off valve flange coming up to melting temps much quicker than the relatively massive intake manifold piece which conducted heat away from the weld area. Despite doing my best to direct the temperature of the flame to the manifold, the heat control was very poor, and I melted away some areas of the BOV flange - some where the v-band clamp touches, and one melt through was so bad even part of the critical o-ring sealing surface fell away! :shock: By the time that happened, I knew what I was doing just wasn't working, and so I stopped before the damage became irreversable. I then came up with a new strategy: I would try pre-heating the manifold to 400 degrees F in an oven, then see if the larger piece would melt easier. I used a smaller flame and less heat. The pre-heating method worked so well, I manage to pull off a perfect 360 degree weld that perfectly fused and sealed the inside diameter of the blow valve to the plenum! :) The molten puddle was much easier to control. I'll have to remember to pre-heat more often when welding dissimilar metal thicknesses. I also successfully built up a weld bead to replace the areas that had fallen away. I'll have to shape them carefully with a file to restore the original surfaces.
The air inlet flange is coming along nicely. With a hole saw, I made about a 2" hole in the face of the air inlet flange. I'll enlarge that to at least the ID of the 2.25" boost tube to allow me to move one step up from 2" boost tube size if I wanted, and the larger hole will also give me better access to inspect and clean out the inside of the plenum. To accomodate the larger hole size, I am leaning towards using a 4-bolt (trapezoidally shaped) sealing flange instead of a 3-bolt / triangular shape. The material where I'll need to drill and tap one of the bolts is a little thin walled and I might only get about 1/4" of threaded meat though - worst case scenario is to add more threaded area, I'll need to cut the section away and replace it with a thick aluminum chunk in its place.
I am trying to figure out what to do with the boost tubing. Here's what the old configuration of the engine bay and boost tubing looks like:
(http://www.imagestation.com/picture/sraid114/pfaf975d1f184d87477d0fb04dd63f80b/f8d3edbb.jpg)
The intercooler outlet diameter is 2.25", and the old configuration of boost tubing has the air go through a crappy nonreinforced rubber 90 degree hose (would really like to get rid of this) before transitioning down to a 2" tubing size. Even though I found the intercooler and boost tubes weren't highly restrictive after installing them as measured by my boost gauge, I'm thinking a little airflow optimization here might be worth my while. Not sure yet if I'll stick with 2" OD boost tubing to the intake manifold, or step it up to 2.25" OD.
Jake... meant to do this days ago. But do you have a picture of how you did your radiator fan setup and puller for the intercooler? I'm thinking of ditching the stock fan configuration and in this pic I can almost make out the radiator...but not quite.
Man...Zonker's car is crazy. I remember seeing that a long while back! have a mk2 16v manifold just sitting here if anyone wants to play someday... :)
Joe
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Joe - check out this thread on the old forum:
Fan on a FMIC, anyone? (http://www.hostboard.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=4037&t=676)
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I have basically finished the air inlet flange now. It turned out really nice. It's a roughly symmetrical trapezoidal shape and the bolt hole I was worried about possibly not having deep enough threads I think is going to be fine after all. I also already cut out a flange to bolt onto it out of 1/4" aluminum plate which eventually will get the boost tube coupler brazed to it. I carefully hand filed both mounting surfaces to try and make them flat, and boy was I pleasantly surprised when I initially test fitted those surfaces together... how tightly they mated together and how smoothly they rubbed against each other you would think they were made with a milling machine. :) I think with a little silicone it is going to seal very well.
The BOV mounting flange has also been SAVED! :) The surfaces where the o-ring and v-band clamp touch are filed down and restored very closely to their original contour. An initial test fit of the BOV mounted to it looks good, but I may want to pressure test it before I run it.
I also got some new supplies and tools for this project. All of my old plumber's rubber couplers and bends will be getting replaced with straight silicone transitions and couplers and 2" aluminum mandrel bent tubing. I also am getting some new supplies to polish what I can easily reach of intake manifold runners: some cross-buffs and also some 80 and 120 grit flapper paper (emery cloth strips placed through a slot in a rod.)
Edit: here is a picture of the 8" long flapper stick polishing tool I made out of a 1/4" steel rod:
(http://www.imagestation.com/picture/sraid197/p938fbccf2e0b3bfe5d993711bf3512d4/f0fa594b.jpg)
The stiffness of the sandpaper as well as the centrifugal force forces the paper out to make contact and conform very well with the walls of the runner... Perfect for runner polishing!
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Sounds great Jake :D Can't wait to hear the reults of all your labour.
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The intake ports are coming along...
just port matched:
(http://www.imagestation.com/picture/sraid197/pffff8e54559e1c2cbeaaefe6926acebb/f0fe54ee.jpg)
after 60 grit flapper paper in an 8" rod:
(http://www.imagestation.com/picture/sraid197/p6104c3cf4052325c6aae6bed129d6c19/f0fe54e2.jpg)
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Looking good! Now stop teasing and show us the whole thing. :P
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I can show you how the plenum is looking:
(http://www.imagestation.com/picture/sraid197/p99f700d4eed499041fb166092d458502/f0fa5a48.jpg)
I'm pretty pleased with how that boost tube inlet flange is turning out. I may weld and file on it a little more, but it's just about done. You can also see I sawed open a big hole in the plenum so I can reach my polishing tools into the cyl 1 and 2 runners. I'll later make a plug and weld that hole shut. (The BOV opening provides a convenient hole to reach runners number 3 and 4 for polishing. :P )
You'll have to wait to see the whole thing completed though, because I just work on it a piece at a time, and I still have a lot of work left. To say this project is a challenging fabrication project is an understatement. There are times when I feel I took a step backwards!
I've been having some problems working on this manifold because of how closely VW cast the EGR plumbing to the runners. I cut and filed off all the EGR plumbing, but the way it was cast it just comes too close to the ports in a couple spots.
(http://www.imagestation.com/picture/sraid197/p6cb642ef666708225f28592512ced74b/f0fa5c46.jpg)
Here you can see the transition of the plenum to runner #3. It's just barely in the light, but if you look in the upper left corner of the runner, you might be bale to see where the is a "bulge" sticking into the runner. It is cast that way on purpose so the EGR passage didn't poke through into the runner! It's very thin right there.
There was another spot where the close-routed EGR passage caused problems, on runner to cylinder number 2 it came very close in one spot. There were casting/oxide voids here making the metal very weak. Long story summarized, in trying to fix it I cut a corner in prepping the surface for welding it, and I just made it worse, making a molten blob of metal droop down into the runner. In trying to clean that up I accidentally broke through all the way in one spot with a small crack, so now I've got to weld it to repair it again. :roll:
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Your doing a fine job, keep it up, people don't realize how much of a learning curve there is and what kind of time it takes to build somthing custom, I will say this, it gets easier everytime you do it.
However after watching this buildup I have decided that for myself, I will never modify a VW intake to fit, I will just go straight custom with all new Al. if for no other reason then it takes so much less effort to weld.
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I really haven't had much problem fusing to the cast aluminum VW manifold material with my latest welding techniques, I really only get bitten when I try and cut a corner. Which is usually when I've just successfully completed a weld, and the piece is already all heated up and I've still got the welding equipment in hand, torch blazing, and I get a spur of the moment idea "this metal is welding so nicely, why don't I just weld this one other spot I've been meaning to get to..." without having properly surface prepped it (which would need to occur much earlier in the process.) That is where the surface oxides can give me trouble with getting proper fusion. I am also obviously really steep on the learning curve here with this whole oxy-actyelene aluminum welding thing... :wink:
Anyway I'm happy I'm using this manifold opposed to scratch fabricating, I think it would have been tremendously more work to do that, not to mention the material cost would have been a lot more for the mandrel-bent tubing so wouldn't have worked for my budget very well. This A1 gasser manifold has the right shape and it seems appropriate features (plenum volume, etc). A feature that would be really hard to duplicate with a scratch-fabricated manifold is the very nice and gradual taper in the runners, which seems to occur throughout their entire length. To duplicate such a taper in a straight section of a scratch fab'ed manifold, you'd need to spend a lot of time custom forming sheet or turning off lots of material on a lathe to end up with the tapered shape, and I don't know how it would be possible to make it bend while tapering at the same time like the stock cast manifold runners do.
My new boost tubing materials have arrived! (A couple silicone transitions and aluminum 90 degree mandrel bends.) Merry early christmas to myself! :P Won't be making any more progress with this though probably until later in the holiday season... got a busy holiday schedule planned. It's not like I'm in a real hurry to get it done anyway though, with the weather being as miserable (rainy, overcast, wet, etc) as it is, I probably wouldn't have a good opportunity to test it anyway. This is not a short term, "instant gratification" project. But at least if it ends up successful, I hope to be happy enough with what I've made that I will have no need to consider any future iterations. That's why I'm going to the effort of doign it right... IE: making it look good, polishing the runners so they flow well, doing very careful work not just slamming it together as quickly as possible, etc.
Seattle winters are very rainy and the days are also pretty short. Sucks for a welding project, where I need daylight to help see what I'm doing, and when I need to do my welding outside for ventilation. And I am doing all this just for fun anyway, so I just do a bit here and there.
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Hey guys I love this post by fspGTD
anyway I know that it might not be a real long runner intake manifold but has anyone tried a TDI intake manifold? I got one this week since it will bolt right up and thats what i will be usiing for a turbo intake
later
Justin
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It's got the big 1.9 style ports so it won't match up very well unless you port the head (if it can be ported that far).
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i always thought that runner length didn't make much difference on boosted cars
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Found a picture of a 1Y manifold.
(http://194.242.159.246/brickyard/forum/uploads/images/andyluffs/2005-06-08_111450_DSCF1432.JPG)
Same port shape as AAZ/TDI (D-shaped)
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In situ on a mechanical TDI of Simon Cooper of Central VW fame.
(http://www.centralvwaudi.com/images/eng2.jpg)
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May also be of use.
http://www.centralvwaudi.com/tdi/tdi2a.htm