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Engine Specific Info and Questions => IDI Engine => Topic started by: moTthediesel on March 28, 2009, 06:23:11 pm
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After years of rust work on my diesel Porsche 356 project, I'm finally putting the mechanicals together. I've spent a good bit of time lately working on a VNT controller for my 1.6 Quantum engine. While mine is the same in principle as others seen on this board, in execution it's quite different. While I guess it doesn't have much application to front drive VW's, if any of you are interested I've posted a few pictures and will try to describe it's workings.
These cars had solid rod throttles and while I guess I could have patched a bowden cable on, I decided to stick with old time rods and bell cranks. This car has a very small engine compartment and there is a lot of equipment and plumbing to cram in there, so I decided to fit the boost control can and vane control mechanism in the space between the long runner GTI intake manifold and the cam cover. That's air space that would have no other use.
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101VNTcontrol0001.jpg)
I fitted a shaft along the back of the firewall behind the head that pulls the fuel control with a bell crank and rod. On that shaft is a cam which acts on a rocker with a central pivot attached to the intake plenum. The other end of the rocker pushes down a rod that goes through the manifold web and closes the vanes.
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101VNTcontrol0004.jpg)
I'm fooling with cam profiles now, but the idea is that the vanes will only be closed by the last 25% or so of throttle travel. This will allow the vanes to be controlled mostly with the "loud pedal", and to remain open in most steady-state driving, only closing when the helmsman calls for flank speed. For further boost control, a can is fitted that pivots up the cam follower when the set level is reached. I used the standard vacuum can that came with the VNT, but fitted a compression spring to force the diaphragm into the "full vacuum" position. Boost pressure then extends the control rod, lifting the cam follower and allowing the spring loaded vane control rod to return to the open position.
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101VNTcontrol0002.jpg)
Crazy complicated? Maybe, but it fits where it has to, and it seems to do what it needs to. I'm still at least a couple of weeks away from running the engine so no trials yet. I'd be interested to hear what anyone thinks about it.
moT
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Pics don't work!
Good to know you are continuing on this project. I've recently gotten involved in 356 Restoration with a guy named Lowell Sivey, he's one of the best at this. Here's a car we are nearly finished with:
(http://lh6.ggpht.com/_mDxOuTI25gI/SceB8_OvfpI/AAAAAAAACEw/PlnH3GpgK7E/s800/0322091401_01.jpg)
It's a 55 Carrera. We've got 3 more in the shop that will be next. The one on the rotisserie in back is the only one of it's kind in the USA- the owner wants it done by next year. :shock:
I'm really interested in your project, keep it up!
Brendan
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good lord that's sexy!
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Pics don't work!
Good to know you are continuing on this project. I've recently gotten involved in 356 Restoration with a guy named Lowell Sivey, he's one of the best at this. Here's a car we are nearly finished with:
(http://lh6.ggpht.com/_mDxOuTI25gI/SceB8_OvfpI/AAAAAAAACEw/PlnH3GpgK7E/s800/0322091401_01.jpg)
It's a 55 Carrera. We've got 3 more in the shop that will be next. The one on the rotisserie in back is the only one of it's kind in the USA- the owner wants it done by next year. :shock:
I'm really interested in your project, keep it up!
Brendan
HOLLY HELL!!!!!!!!
I absolutely LOVE that car!!!
PLEASE please PLEASE do a build up thread? I want more pictures.
I painted a couple of those back in the day. Full metal cars. Nice stuff.
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You know, I have been looking at one of those long runner intakes and tying to figure out how the hell you would get the manual controls to work for a vnt setup. I was wondering if there was adaquate room to drill through between the runners to run some sort of setup. I guess there is. Have you, or anyone else for that matter, seen any other mechanical vnt linkage setup's that involved the long runner intake like the above gti unit or a 1Y / 1X ? I am guessing the turbo would need to be re-clocked like Andrew did on his Mercedes gt22??v install, due to the fact that the runners go way back behind the head.
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Well, I finally got the pictures to load in a visible size, sorry, I'm new to photobucket.
My car is a plain old C coupe, sadly, not a Speedster :(
Here's a pic of the rear of the car, and one of the 2-1/2" ss exhaust.
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101whitestripes0002.jpg)
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101exhaust0003.jpg)
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:( You're my new hero. A diesel, in a super-sex Porsche 356? I have wanted a 356, any 356, since I first learned what a good looking car was...
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Well, I finally got the pictures to load in a visible size, sorry, I'm new to photobucket.
My car is a plain old C coupe, sadly, not a Speedster :(
Nothing wrong with that! We've got a C-coupe in the shop too, it's a '65- with disc brakes all around, the C-coupes are my favorites. :) Not to mention a little more practical.
After looking over the pics about 5 times and re-reading your description, it finally sunk in, pure genius! Other than the modified deck lid, did you have to modify the engine bay much? Are you using the stock Porsche Transaxle?
This looks killer, I can't wait to see it driving!
Brendan
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HOLLY HELL!!!!!!!!
I absolutely LOVE that car!!!
PLEASE please PLEASE do a build up thread? I want more pictures.
I painted a couple of those back in the day. Full metal cars. Nice stuff.
Don't really have a build up thread, since it's not my car. I also don't want to thread-jack but I'll quickly post up what I've got.
Here's where it was when I first started working for this guy- well, actually it was in primer but we painted it soon after. The body work prior to this was extensive. The owner bought it in Mexico, some crazy Mexicans had hacked up the doors to put in power windows (???) and there was prior bodywork where they had cut the front of the car off and nearly cut through the serial number. Amazingly the engine was still there.
(http://lh6.ggpht.com/_mDxOuTI25gI/SPyC2RJY8MI/AAAAAAAABsk/AWUOP0Ae_Hs/s400/1019081538.jpg)
Later details:
(http://lh3.ggpht.com/_mDxOuTI25gI/STP1YeOyZ6I/AAAAAAAAB1U/k9-G6-XOVRM/s800/1130081543.jpg)
It somehow still had the original badges so we cleaned them up and re-used them.
(http://lh4.ggpht.com/_mDxOuTI25gI/STP1iH8gZVI/AAAAAAAAB1g/fDlauUrh5JA/s800/1130081542a.jpg)
Carreras' had dry-sump oiling from the factory.
(http://lh5.ggpht.com/_mDxOuTI25gI/STP1vW2UXCI/AAAAAAAAB1s/ez7-qglQm-c/s800/1130081542.jpg)
And bigger front drums.
(http://lh6.ggpht.com/_mDxOuTI25gI/STP2BKz6nBI/AAAAAAAAB14/XnjlBJm154M/s800/1130081526.jpg)
Original gauges!
(http://lh4.ggpht.com/_mDxOuTI25gI/SceBr0sJ-5I/AAAAAAAACEo/IwMmRpqJ77Q/s400/0315091504_03.jpg)
(notice the '65 in back)
Sadly, we aren't building the engine for this one, the owner has his own engine guy. He's got almost $200K!!! in the engine alone. The Carrera's had the crazy 4-cam aircooled engine, not the typical pushrod Beetle-like engine. (though they were not the same) The Carrera engine had roller bearings, shaft-driven cams, dual distributors, dry sump oiling, etc... pretty high tech. The car will be worth upwards of $700,000 when it's finished.
Sorry to moT, I don't want to take away from your post, if you want me to take down the pics, just let me know.
Brendan
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We've got a C-coupe in the shop too, it's a '65- with disc brakes all around, the C-coupes are my favorites. :) Not to mention a little more practical.
After looking over the pics about 5 times and re-reading your description, it finally sunk in, pure genius! Other than the modified deck lid, did you have to modify the engine bay much? Are you using the stock Porsche Transaxle?
The motor fits fine with little modification required. I didn't really need to put that hump in the deck lid. I was trying to put the radiator there, but it didn't work out. Now it's mounted on the right side of the engine with an air scoop and duct from under the car. It's an aluminum two row "Scirocco" rad from Summit, supposed to be good for 600hp. :lol:
The trany is a stock Porsche 741 four speed with a Kennedy adapter and a Kennedy stage 2 clutch. I'd like to add the super tall 4G top gear, but it's not in the budget right now.
The engine is a fresh rebuild with a Giles pump and GTD nozzles and the VNT is blowing through a 944 turbo intercooler. I'd like to see about 110hp and 160f/lb at 15psi without straining anything too much. With this car's weight (about 2k#) and aero shape I'd expect to see 50+ mpg too. Lots of plumbing and wiring to do, but it should be ready to fire up in about 2 weeks -- YAHOO!
moT
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Sorry to moT, I don't want to take away from your post, if you want me to take down the pics, just let me know.
Brendan
Hell no! That's a great looking car and I'm glad to see it on here --
Those 4 cam Carrera motors are awesome, but for $200k he still won't see 160ft/lb @ 2500 like I will for less than a grand :wink:
moT
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Hell no! That's a great looking car and I'm glad to see it on here --
Those 4 cam Carrera motors are awesome, but for $200k he still won't see 160ft/lb @ 2500 like I will for less than a grand :wink:
moT
Heh heh. I bet he will. I guess the guy is putting a crazy turbo setup on it. He's got more money than brains I guess. This is the 3rd car that Lowell has restored for him, he has a total of about 12 356's I guess, about 6 of them are Carrera's of some flavor. The C-coupe also came from him, though Lowell bought that one.
I'd also say that you will probably be making more HP and torque than what you thought though, so that car should fly!
Brendan
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I've NEVER seen a 4 pot Carrera with a turbo -- I sure hope he's got everything engineered properly, that has the makings of one very expensive grenade job!
moT
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Hey Mot,
I don't understand exactly how that works.
It sounds like it's connected to the throttle cable but I can't see how.
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Hey Mot,
I don't understand exactly how that works.
It sounds like it's connected to the throttle cable but I can't see how.
There is no throttle cable in this car, it has a solid pull rod from the A pedal back to a bell crank on the transmission. From there another pull rod curves up over the axle and then up to a bell crank on the rotating rod behind the head (sorry, you can't see that in the pics). That has still another bell crank that pulls the fuel lever on the injection pump. The rod has a cam on it that lifts one end of the rocker mechanism (see in the bottom picture above) as it turns. The other end of the rocker pushes down on the vane control rod and closes the vanes.
The advantage to this (as I see it) is that by experimenting with the shape of the cam you can adjust when the vanes close relative to pedal movement. Also the vane movement is positive in both directions so that it's less likely to stick either way.
I had trouble with the curved rod from the trany up to the engine, it would tend to straighten out when pulled which made for notchy throttle movement. The answer was to truss the 1/4" curved rod with some 3/16" rod as you see here, nice smooth, progressive movement now!
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101paintedparts0012.jpg)
moT
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Here's the control mechanism i'm currently working on. If I could clone myself it would be done but the government says I have to wait...
(http://images.thesamba.com/vw/gallery/pix/539322.jpg)
I still need a flip flopped vacuum actuator & it'll take a bit of tinkering with the arm length & pivot point to get the travel right.
mothediesel, are you using a wastegate actuator there? I do like it!
You've been holding out on that build for way too long!
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I really like this one!!
Here's the control mechanism i'm currently working on. If I could clone myself it would be done but the government says I have to wait...
(http://images.thesamba.com/vw/gallery/pix/539322.jpg)
I still need a flip flopped vacuum actuator & it'll take a bit of tinkering with the arm length & pivot point to get the travel right.
mothediesel, are you using a wastegate actuator there? I do like it!
You've been holding out on that build for way too long!
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I wish I had clones also...
Andrew
Oh my!
Not of me. The world doesn't need anymore dicks! One of me is enough...
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Hell no! That's a great looking car and I'm glad to see it on here --
Those 4 cam Carrera motors are awesome, but for $200k he still won't see 160ft/lb @ 2500 like I will for less than a grand :wink:
Man, for $200K I'd drop a Pratt& Whitney PT6 with 550 hp burning JP5 !! You'd need a really big fuel tank, but on that "budget" it should not be an issue.
Outstanding project, though. Really good engineering you've done. Keep the updates coming.
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Here's the control mechanism i'm currently working on. If I could clone myself it would be done but the government says I have to wait...
(http://images.thesamba.com/vw/gallery/pix/539322.jpg)
I still need a flip flopped vacuum actuator & it'll take a bit of tinkering with the arm length & pivot point to get the travel right.
mothediesel, are you using a wastegate actuator there? I do like it!
You've been holding out on that build for way too long!
That's an interesting mechanical logic circuit, I'll have to think about it for a while!
I'm not using a wastegate actuator, I'm using the vacuum can from the VNT, but I used a spring to compress the rod into the can. Then, by introducing boost pressure to what was the vacuum port, the rod is forced out, as in a typical wastegate can.
If there is interest here I'll post some more build pictures as I go along. Next up on the punch list is the plumbing for the 944 intercooler.
moT
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Yes, me too. I'm working on a version of that one for my next project as well. I wish I had clones also...
Andrew
How far along are you on this? Its been a while since we first talked about it & I'm excited to live vicariously. Mine got put aside for an m-tdi...
moT, how much travel are you getting out of that vacuum actuator? Thats a great way to turn it into a boost controlled actuator without having to get into its guts.
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I have build an electronic VNT control.
It can work with a tdi injector to calculate the injection time OR with a simple variable resistor on the pump.
You can use the vacuum and N75 or AAZ valves for idle ,etc.
I can put the schematic for those who are interested.
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I can put the schematic for those who are interested.
S'il vous plait !
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I just don't want anyone selling it...
It is open source not for sale! I made correction on these schematics... so it's supposed to be even better to the one I already built.. but they might be a bug.
Check the schematic if you want to try it very soon. In about 2 weeks I will build this new version and report. I am 99% sure it's ok.. but we never know.
Have fun.... you will need to program a chip to make everything work. I might send them already programed.
Selenoid 1 and 2 are where the valves or N75 needs to be plugged.
SL4 would be where you plug the variable resistor on a pump.
SL1 is where the tdi #3 injector plugs in
THe system can control presure starting at 3psi... a symetric voltage supply would be needed for 0-3psi.. I don't think it is usefull
N.B. If you want to instal a variable resistor on the pump, part 2 of the schematic is not necessary.
(http://img.photobucket.com/albums/v319/bareil76/part1.png)
(http://img.photobucket.com/albums/v319/bareil76/part2.png)
(http://img.photobucket.com/albums/v319/bareil76/part3.png)
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Thanks guy, for clearing that up.
I understood everything about how the boost can worked but couldn't figure out how the throttle cable hooked to it.
sooo the roller rides on a cam that is moved by the accelerator cable,..
any pics of that piece?
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How far along are you on this? Its been a while since we first talked about it & I'm excited to live vicariously. Mine got put aside for an m-tdi...
I'm juggling a few projects and so it's hard to tell how long things will take. But, I've got the engine for that project assembled as a longblock. I'm currently assembling an injection pump and then the vane control system is the last bit to do before shoving it all in the car. I'd guess that will all happen in the next 2-3 weeks.
Andrew
Sweet, can't wait to see it!
Hey, pretty spanky circuit, do you have a logic diagram for its operation for us mere mortals? Do you plan on taking it to the PCB level? Those diagrams made me want to just go find an ECU for my m-tdi! :wink:
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I think a will make a DIY post of it.. I will include the PCBs, materials needed with price and how to actually MAKE a printed circuits with few chemicals.
Lot of fun!!
I think about 50$ to 70$ to build it the first time (about 40$ in parts) and 4-6 hours to develop, drill the MANY holes and solder everything.
I will take picture when I make the next model... waiting for some parts.
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Hey
This is very interesting and I look forward to DIY post,
Guy
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I think a will make a DIY post of it.. I will include the PCBs, materials needed with price and how to actually MAKE a printed circuits with few chemicals.
Lot of fun!!
I think about 50$ to 70$ to build it the first time (about 40$ in parts) and 4-6 hours to develop, drill the MANY holes and solder everything.
I will take picture when I make the next model... waiting for some parts.
i'd probably test the circuitry on a breadboard first and then get one of those online places to fab up some PCB's. the more you buy the cheaper they are. that might be the best way to go :)
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When I made my low coolant level/overheat warning light circuits for the Rabbits,
I used these guys:
http://www.expresspcb.com/
They had some software to download that made it real easy to draw up my own board.
Sent it to them with some cash and got some boards in the mail.
Worked great for the small test batch I made to work out any problems.
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Thanks guy, for clearing that up.
I understood everything about how the boost can worked but couldn't figure out how the throttle cable hooked to it.
sooo the roller rides on a cam that is moved by the accelerator cable,..
any pics of that piece?
Hard to get a good picture, but here's a couple.
Fuel pull rod:
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101paintedparts0005-1.jpg)
VNT cam:
(http://i651.photobucket.com/albums/uu236/motthediesel/2004_0101paintedparts0011.jpg)
moT
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Sorry to hijack but a little question on the throttle actuation of VNT.
If the vanes are only fully open when throttle is fully pressed, what happens at say half throttle on a hill?
I am planning on running the VNT off throttle and boost control via external wastegate. But I want to ensure that on the 400m climb I drive to work every day I don't have to have full throttle depressed to create boost?
Or does the partial opening of the vanes direct enough gases to spin the turbo for partial boost?
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Without the vanes closed it will act like a typical wastegated turbocharger.
Yes so it will still turn the exhaust wheel enough to generate boost but won't be as responsive as when vanes are fully open?
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That should be good enough, I will be running a 1.6 bottom end with 1.9 head, NA exhaust manifold made to work with my Land Rover BV50 hopefully blowing through my NA intake but with alloy top instead of plastic. :D
Want power when foot down but economy when not ;)
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On another note, MoT, what's up with the red dust on and in everything? I'm hoping it's not inside the valve cover area from the open hole where the oil separator should be...
That's overspray -- I painted the car in the same hellhole of a shop that I do everything else in. Had a tarp over the engine, but it still got up in there. Doubt it will do much harm.
moT