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General Information => General => Topic started by: R.O.R-2.0 on June 10, 2012, 12:43:56 pm
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So, im going to be building a new intake manifold soon..
and ive been kinda looking around, to see whos manifold i want to copy..
ive been toying with the idea of dual plenum, but it seems easy to mess up your calcs..
a single plenum would be easy enough, but are they really that good for even boost distribution to all 4 cylinders?
heres a few pics ive pulled up online, just for ideas.
this ones a single plenum, looks easy enough to build. i dont like how the runners meet the flange at an angle tho. looks like its not ideal.
(http://img26.imageshack.us/img26/2877/customstainless2.jpg)
(http://img832.imageshack.us/img832/1503/customstainless.jpg)
i cant get any pics of a PP intake, but it uses a stock lower section, and a modified upper section. i like his design the best. apparently the lower half of the stock intake is not as restrictive as it looks..
im really leaning towards basically just copying Daves manifold.. not a 100% copy, but close..
anyone know the size of the slit in the pipe between the main plenum, and the intake plenum?
or does anyone have a BETTER idea than any of mine? i dont have much space to work with..
heres a shot of how close the manifolds are:
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000540.jpg)
i really dont have much room to work with. i think the only option i have is to modify a stock intake manifold..
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(https://lh6.googleusercontent.com/-N1eNzmxB-YQ/T9DCElbTdlI/AAAAAAAAEoM/YEQh0ZzQR1M/s800/2012-06-02_12-42-28_626.jpg)
why not be like the toyota one in pic... this added to itb on a 16 rocco... basicly a header for a intake??
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(https://lh6.googleusercontent.com/-N1eNzmxB-YQ/T9DCElbTdlI/AAAAAAAAEoM/YEQh0ZzQR1M/s800/2012-06-02_12-42-28_626.jpg)
why not be like the toyota one in pic... this added to itb on a 16 rocco... basicly a header for a intake??
because i have SEVERELY LIMITED room to work with. did you see how little clearance there is between the intake and exhaust manifolds? there is roughly 1" from the back of the stock manifold to the tubes of the turbo header.. the picture i posted, is of my engine bay. theres no way on earth you could fit a manifold that doesnt have a shape similar to the original..
so, whatever manifold i use, has to be very low profile.. the turbo header ive got is made to be used with an OEM style pancake intake manifold. it works nicely with a PD, or stock TD, or stock AAZ/TDI intake as well. but it has to be a flat intake. thats why i was favoring the PP design, since it uses the lower half of the existing intake manifold..
also, spacing on the toyota manifold is all wrong for any sort of 8v.. i believe it was even a slight bit different from the spacing of the 16v head..
i dont have near enough room for a toyota header intake manifold..
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missed what i was saying.. design your own "header" style manifold.. up over to the room on top of the turbo? all equal length runners, big collector to branch off of? the pic was for design idea.. know no room for that..
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missed what i was saying.. design your own "header" style manifold.. up over to the room on top of the turbo? all equal length runners, big collector to branch off of? the pic was for design idea.. know no room for that..
dunno how i would make tight enough bends to come off the intake ports and not hit the header. even cast elbows are too wide of a bend..
there is literally NO ROOM for anything bigger than whats on there now. if it was any thicker, or different in any way, it would be basically IMPOSSIBLE to get the bolts out of the manifold. and how it is now, you have to install the header first, then the manifold. removal is exact opposite.
basically, i NEED the tight bends of the stock manifold ports just to clear the turbo manifold..
i like the idea of a dual plenum more than a tubular intake anyways.. alot less work to copy daves manifold, than to roll my own.
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you have round not d shape right?? if round you can do a 70-90* angle cut on the pipes goin into the flange at the head so the basiclly go verticle up... now if d shape not so easy... but same idea applies..
you could also cut the runners off the one your using.. extend them up and do what you want.. but IMO if you wanna seek 100% same for each.. i do not think any plenium style will ever be 100% even..
why not add a intercooler into the mix?? runners extended up.. tipped back, intercooler, flange to go directly to turbo?? intercooler eliminates plenium.. no long boost pipes for lag.. so on...
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I think your on the right track with starting with the stock one and building up from there. Wow, that's tight.
I found this place, it might give you some ideas.
http://www.rossmachineracing.com/intakepartspage.html
And this intercooler end tank from Treadstone.
http://www.treadstoneperformance.com/product.phtml?p=1311&cat_key=449&prodname=Treadstone+EV125
This would allow the air to flow more evenly across and into the cylinders.
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you have round not d shape right?? if round you can do a 70-90* angle cut on the pipes goin into the flange at the head so the basiclly go verticle up... now if d shape not so easy... but same idea applies..
you could also cut the runners off the one your using.. extend them up and do what you want.. but IMO if you wanna seek 100% same for each.. i do not think any plenium style will ever be 100% even..
why not add a intercooler into the mix?? runners extended up.. tipped back, intercooler, flange to go directly to turbo?? intercooler eliminates plenium.. no long boost pipes for lag.. so on...
ive got an intercooler. its a front mount. hooked up even. what does that have anything to do with wanting a different intake manifold tho?
i dont have an intake flange, or a way to cut one. and im not going to buy one, so that pretty much counts out the custom manifold..
if dave cross thought it was good enough for him, then its good enough for me. basically, from where i am now, i can not get ANY WORSE of a manifold.. i have the worst possible designed manifold on the planet.. anything i do, will be better than what its got..
i still think dual plenum will be the ticket. how would it be WORSE than a single plenum? the slit between the 2 plenums is to keep the pressure equalized..
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why intercooler... if your trying to even out the flow of air to the head.. using a intercooler as plenium should do that...
your original question is on making a manifold that solves improperflow... my suggestions do that.. :P plenium designs.. duel/single.. slit or not.. i cannot see how 1 end will not have less/more then the other.. hell why not weld up the middle hole.. add hole on top of 1-2 and 3-4 and Y the 2 together??
now.. for my stupidity... if you have no way to cut the stock one.. how do you plan to make a custom one? the flange to the head is the biggest piece of the puzzle..
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why intercooler... if your trying to even out the flow of air to the head.. using a intercooler as plenium should do that...
your original question is on making a manifold that solves improperflow... my suggestions do that.. :P plenium designs.. duel/single.. slit or not.. i cannot see how 1 end will not have less/more then the other.. hell why not weld up the middle hole.. add hole on top of 1-2 and 3-4 and Y the 2 together??
now.. for my stupidity... if you have no way to cut the stock one.. how do you plan to make a custom one? the flange to the head is the biggest piece of the puzzle..
its not that i cant cut a manifold flange, i just dont feel like starting from scratch. and im not going to pay big bucks for a lazer/plazma/cnc cut flange.. dave cross built 193hp with a stock turbo, and this type of intake manifold..
Chris, do you KNOW what a passenger performance intake manifold is? they are SUPER easy to make.. i can cut the top of my manifold off with the band saw i have in my shop.
(http://i702.photobucket.com/albums/ww28/Dubsmoke/lightmanifold.jpg)
(http://i702.photobucket.com/albums/ww28/Dubsmoke/3rdmanifold.jpg)
he cut the manifold parallel with the valve cover rail, and just extended the original plenum.
i also thought about cutting the top of the intake manifold off, extending the plenum a bit, and just adding another inlet. so i would have 2 inlets on my intake. it would basically be a 1->2->4 manifold, kinda like a backwards tri-y header.. that should distribute the air fairly evenly over all 4 cylinders..
im just not happy with the stock intake. cylinders 1 & 4 have got to be just STARVING for air. it biases #3 really bad. there was a light film of oil in the intake manifold and charge piping, but it only got fed into the runner for #3..
i used to always get a carbon streak out #3 exhaust runner as well, and im sure it was because any oil that comes thru the charge piping, was ingested by #3 cylinder, not any others.. the other 3 runners of the manifold werew CLEAN.
another thing, the 1.5"x1" opening of the intake manifold & elbow can NOT FLOW GOOD..
again, i have VERY LIMITED space to work with here..
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000545.jpg)
and, another shot of everything.. intercooler piping was kinda challenging this time, having both pipes on the same side..
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000542.jpg)
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Kev, is that marine exhaust tubing you are using as your intercooler pipes?
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Kev, is that marine exhaust tubing you are using as your intercooler pipes?
well, most of the charge piping is 3116 Caterpillar coolant pipe..
then that piece connecting the intercooler to the intake, yes, thats marine billows hose.. that stuff works good to make charge pipe couplers out of also.. but, go figure, my family builds custom boats, so i have access to lots of left over scraps of things that were used for boats they built.. and the Racor filter, its off a boat as well.. so is the pink gates heater hose..
it withstands oil, pressure, water, anything. and it has wire inside it so it doesnt expand real bad with boost..
the piping is FAR from ideal. it was just thrown together to work..
once i have a turbo setp that i feel comfortable running, i will go to an exhaust shop and have some tubes bent for the car..
only reason i havent gone with real boost tubes yet, is because i keep swapping out, or killing turbos...
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Factory BOV, and secondary manifold inlet are now both deleted..
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000560.jpg)
getting ready to make it a dual plenum
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000561.jpg)
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000559.jpg)
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If I remember right it's not the same distance from the near end to the far end. I think the front part of the slot is a little wider than at the end. You can test this for even flow by using a leaf blower and holding it above a large tub (bathtub?) of water and see the ripples that are created are coming out even from the manifold holes. Change the slot as necessary to get even output.
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If I remember right it's not the same distance from the near end to the far end. I think the front part of the slot is a little wider than at the end. You can test this for even flow by using a leaf blower and holding it above a large tub (bathtub?) of water and see the ripples that are created are coming out even from the manifold holes. Change the slot as necessary to get even output.
those are just lines on the aluminum. not sharpie lines for the slit i cut. those do look a bit like sharpie lines tho! the slit starts at about ~1/2", and tapers down to ~1/8"..
PICS TO FOLLOW!!
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So, i finished it up at about 11pm last night..
GOD DAMN IT TAKES A LOT OF HOURS TO BUILD ONE OF THESE!! i can totally see why custom manifolds, like Nubworks, are SOO expensive. its because of all the labor/design included in the build..
theres no instruction kits for this kinda thing, no DIY, no nothing like that..
anyways, without further avail..
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000562.jpg)
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000565.jpg)
the slit is NOT parallel, like some people have made.. i wanted the slot tapered, because that is the main function of a dual plenum manifold, is for it to EVENLY distribute boost.
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000564.jpg)
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000563.jpg)
anyways, im not too pleased with the weld quality (dad wasnt here to help me set the welder, and im not practiced in aluminum welding like i am steel.. but thank god, there are grinders to take care of ugly welds.. just wish more people thought like that. you can not make an ugly weld any more ugly, so grind it down.
another thing, the intake note, with nothing hooked to the manifold, rather than the ROAR it used to have, now it sounds MUCH MORE TAME as compared to before..
cant wait to get my linkage setup rigged up, so i can actually build enough boost to see gains from this intake..
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Talk to AKI 76 if you can. I think his mani he made me didn't have near that much taper. I was thinking maybe 1/2 to 3/8...it really isn't noticable unless you are measuring.
I am not dogging, I am just trying to help. Whatever you do I am almost 100% sure it will be better than the VW design. Since you are not doing individual runners it should be less important than if you were.
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Talk to AKI 76 if you can. I think his mani he made me didn't have near that much taper. I was thinking maybe 1/2 to 3/8...it really isn't noticable unless you are measuring.
I am not dogging, I am just trying to help. Whatever you do I am almost 100% sure it will be better than the VW design. Since you are not doing individual runners it should be less important than if you were.
thats what im thinking.. i did ZERO math on the slot. just drew some lines on there that looked good. if it works, it works..
and there is NO WAY IN HELL that i went backwards from what was on there before.. i guarantee that it flows 100% better than stock..
so far, ive had a pancake TD manifold, and a gasser manifold.. i dont see how this one i just built could be ANY WORSE than what ive had on there..
the next manifold will be individual runners.. im gonna actually plan ahead for it tho, buy plenum material, and velocity stacks to weld on the ends of my runners..
i just gotta find another stock TD manifold to cut up now. or else rebuild my AAZ head, and drop that on there.. should just do that, with all the turbo ive got, i should just go for a hybrid..
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Proud of you sir. That cast aluminum is some rough welding. I wouldn't touch it when I blocked my overboost hole. I gave it to my guy and let him cuss it. So much crap in the casting to get a great looking weld, yours look pretty good.
I don't know when you are making your next one, but my machinist has that flow/tumble machine that will show you what needs done to make it perfect.
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Proud of you sir. That cast aluminum is some rough welding. I wouldn't touch it when I blocked my overboost hole. I gave it to my guy and let him cuss it. So much crap in the casting to get a great looking weld, yours look pretty good.
I don't know when you are making your next one, but my machinist has that flow/tumble machine that will show you what needs done to make it perfect.
i have no access to such a machine..
prolly gonna be a joint effort between Josh and I, on the next manifold.. he has connections to EVERYONE/EVERYTHING in Portland..
that overboost protection valve was a *** to block off.. instead of welding a circle over the spot it used to be, i cut it clear off..
for those of you wondering:
CAST ALUMINUM IS A ROYAL *** TO WELD!!! if i were to do it again, i would bake it at 4-500* for a few hours first, to try and neutralize some of the crud in the metal..
anyways, im fairly happy with how it turned out..
ANYONE GOT ANY SPARE TD MANIFOLDS LAYING AROUND?!?!
i need to start stocking up on them now 8)
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I think that slot is backwards and will actually create a severely imbalanced flow. With a straight slot you will end up with the greatest flow near the boost source and the least flow farthest away because air will have been used up in the easier/closer path. To attempt to balance that out, either the outer plenum is a tapered cone with a straight slot or a straight cylinder with a tapered slot that gets larger as it goes in farther. You've done the reverse which will result in almost ALL of the air flowing to #1 and almost none to #4.
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I think that slot is backwards and will actually create a severely imbalanced flow. With a straight slot you will end up with the greatest flow near the boost source and the least flow farthest away because air will have been used up in the easier/closer path. To attempt to balance that out, either the outer plenum is a tapered cone with a straight slot or a straight cylinder with a tapered slot that gets larger as it goes in farther. You've done the reverse which will result in almost ALL of the air flowing to #1 and almost none to #4.
how? the air is going FORWARDS.. with a parallel slot, the air travels forwards. and port #4 is where its going first..
how come EVERY OTHER DUAL PLENUM intake ive ever seen, had the slit cut JUST LIKE MINE? they must all be backwards too..
the way i look at it, is the air is coming in the inlet, and being forced towards #4 end of the intake.. the greatest pressure is going to be over the #4 intake runner. and the LEAST pressure will be at the #1 end, because the boost is being BLOWN PAST that end of the manifold..
everywhere i read online, said that the slot starts LARGER, and taperes to SMALLER.. or else has a tapered plenum, and a straight slit.
there are pics online of manifolds, from PROFESSIONAL companies, with the slot layout JUST LIKE MINE.. the slit starts out bigger, and by the end of the manifold (opposite the inlet) is where the slit is SMALLEST..
maybe your looking at my pics wrong, or you havent had enough coffee this morning..
i just dont see how EVERYONE who made them with a tapered slot, made them backwards.. i did ALOT of looking online. most manifolds use a tapered plenum with a straight slit. i was not equipped to build such a piece..
so, the plenums are BIGGEST at the inlet, and SMALLEST at the far end. just like the slit in my manifold..
HOW DID I BUILD IT BACKWARDS?!
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You may be right. In looking at dual plenum designs my focus has almost entirely been on the tapered cone style. I would do a little rudimentary testing with leaf blower or compressed air as mentioned previously in this thread just to be sure.
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You may be right. In looking at dual plenum designs my focus has almost entirely been on the tapered cone style. I would do a little rudimentary testing with leaf blower or compressed air as mentioned previously in this thread just to be sure.
ill test it.. dont worry.. i just dont have time right now. im leaving for the weekend..
even if its not PERFECT, it cant be any worse than what comes stock..
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I think that slot is backwards and will actually create a severely imbalanced flow. With a straight slot you will end up with the greatest flow near the boost source and the least flow farthest away because air will have been used up in the easier/closer path. To attempt to balance that out, either the outer plenum is a tapered cone with a straight slot or a straight cylinder with a tapered slot that gets larger as it goes in farther. You've done the reverse which will result in almost ALL of the air flowing to #1 and almost none to #4.
How the big boys do it.
http://www.bufkinengineering.com/intake%20manifolds.htm
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Yup I've seen that site. I think i linked it on this forum a few years back. Those are all tapered cone manifolds.
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The way I understand it you do the wider slot closest to the air inlet because the air doesn't want to turn. So by restricting the far end which is where the airflow wants to go, you force it into the near side of the tapered slot. If you used the leaf blower previously mentioned or even a large shop-vac and some "smoke", you should ideally see similar amounts of air coming out of each port at the head flange. I wonder if you could put some large balloons over the outlets and visually see if they expand/fill at approximately the same rate?
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The way I understand it you do the wider slot closest to the air inlet because the air doesn't want to turn. So by restricting the far end which is where the airflow wants to go, you force it into the near side of the tapered slot. If you used the leaf blower previously mentioned or even a large shop-vac and some "smoke", you should ideally see similar amounts of air coming out of each port at the head flange. I wonder if you could put some large balloons over the outlets and visually see if they expand/fill at approximately the same rate?
with BOOST (restriction basically) it will even out the flow even more. both plenums will be charged equally before the port even needs air. i dont see it being an issue. im GOING to try the leaf blower/shop vac before i put it on, but im almost positive ive gotten it pretty close to what i was going for..
i read that whole Audi rally car pic album, studied every pic closely, and then did some more studying.. every design ive seen, was a tapered cone, going from big at the inlet, to small at the end. and saw quite a few manifolds with straight upper plenums, but LOTS of those ones had straight divider slots..
Aki-76 even told me i built it right, so im going to take his word on it 8)
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well, the car runs cooler EGTs, and less boost going down the road.
turbo spools quicker as well.
im going to say that the manifold was a success..
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That's great, glad it worked out. What would you say the before and afters were for EGT's and cruzin boost?
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yes it is odd the amount of people that will leave popcorn welds... 5 minutes of grinding and no one will ever know how horrible it used to look.
sweet manifold i want a similar one, its really nice to hear a before and after comparison of how crappy the stock manifold is haha. i kind of wonder if the dual plenum manifolds on these little engines would make any difference at all. but hey while you were at it why not make it dual plenum right, surely it won't hurt.
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That's great, glad it worked out. What would you say the before and afters were for EGT's and cruzin boost?
it used to run about 700 cruising. now it runs 800-900 going up hills with 8 psi.
used to cruise at about 5psi, now it makes about 3-4.. not a big drop, but enough that i noticed it.
and, it used to make 7-8 psi no matter what, even wide open throttle, with wide open vanes, it usually only made 7-8.. well, i got it to make 15 with the vanes open yesterday..
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Awesome work, Kevin! That manifold turned out awesome!
I'm going to go right now to cut apart my manifold to make a new one, very similar idea to yours. I have an idea that might work to make the upper plenum tapered with very limited tools though ;) I'll see how it ends up turning out though. Worst thing I can do is wreck a piece of aluminum tube and have to buy a new one
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Awesome work, Kevin! That manifold turned out awesome!
I'm going to go right now to cut apart my manifold to make a new one, very similar idea to yours. I have an idea that might work to make the upper plenum tapered with very limited tools though ;) I'll see how it ends up turning out though. Worst thing I can do is wreck a piece of aluminum tube and have to buy a new one
if you need more pics of it, or more of a detailed "how-i-built-it" type of list, feel free to ask.. ive got quite a few pics of it, and if i dont have the pics you are looking for, then i can pull it off in like 10 minutes..
the manifold REALLY DID turn out awesome, and im not trying to pat myself on the back either.. everyone who has actually seen my manifold in person, has not had a SINGLE bad thing to say about it. most people cant believe that I BUILT IT.
i used a band saw, and a welder. that was it. well, a grinder to clean up the metal.. i built this in my HOME shop, not at the school.. the turbo header was a product of the college..
i cut the BOV off as well, and welded a piece over where it was. next time i would just use a LATER model TD intake..
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Factory BOV, and secondary manifold inlet are now both deleted..
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000560.jpg)
getting ready to make it a dual plenum
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000561.jpg)
(http://i702.photobucket.com/albums/ww28/Dubsmoke/P1000559.jpg)
Kevin,
How tall can you go before issues with the hood on the MK2? What is the height from the bolt holes or another point such as top or bottom of the ports that you have. I am going to build one soon and need to know.
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Also with the height question that I still need...Did you use 2.5" ID pipe and if so pm me the details as I have a formula for this and want to see if yours fits in the range.
Anyone know where to get horn shaped aluminum tubing. Like the velocity stacks for a carb only 1-3/8" diameter?
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Harley stacks?
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Those are crazy epensive, but a possibility.
found this but also pricey.
http://www.summitracing.com/parts/SUM-G3029/
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I really want that, and I am sure you aren't giving it away...
What I can give away is some hillbilly cheap info. If you want velocity stacks then look no further. On the cheap and all aluminum. You will have to do some fab work, but if you are building an intake that shouldn't bother you.
Be warned this should make you LOL, but I am serious, this is what my intake will have in the plenum...
http://www.culinarydepotinc.com/p-31242-alfa-022rt-34-stuffing-tube.aspx
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I really want that, and I am sure you aren't giving it away...
What I can give away is some hillbilly cheap info. If you want velocity stacks then look no further. On the cheap and all aluminum. You will have to do some fab work, but if you are building an intake that shouldn't bother you.
Be warned this should make you LOL, but I am serious, this is what my intake will have in the plenum...
http://www.culinarydepotinc.com/p-31242-alfa-022rt-34-stuffing-tube.aspx
lucas, im sure those are some super thin, soft alloy.. i doubt they are going to work that well..
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I have had them in my hand and I would agree they are somewhat thin, but still over 1/16". I am not using them for the entire tube, I am going to use them for the bell end only, welded to a .083" wall 6061 alloy tube. It will work fine. I wouldn't 100% trust them for a structural part for years of service, but they are stout enough I bet it would work for a while. You would be surprised at the force to stuff some sausage :D
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I have had them in my hand and I would agree they are somewhat thin, but still over 1/16". I am not using them for the entire tube, I am going to use them for the bell end only, welded to a .083" wall 6061 alloy tube. It will work fine. I wouldn't 100% trust them for a structural part for years of service, but they are stout enough I bet it would work for a while. You would be surprised at the force to stuff some sausage :D
that would work, just using them for the actual inlet trumpet..
i thought you were going to use them for the runner and all tho..
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Runner and all would be way too small at 3/4". I think they would hold some weight, but I am into trusting the 6061 that the runners will be made of more. I dont know what alloy the stuffing tubes are made of, but it is stout. I am kinda impressed with it...alas it will work for the task at hand for sure.
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And as an added bonus when you are out hunting you can make sausage with your engine. Just going to taste a little, well like diesel.
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I think onced I am ready for a better intake I will flip the exhaust manifold and get a stage 1 scientific rabbit manifold, they're only 125, can't beat that