3.2 VR6 OEM+ intake manifold project.

[BOUDAH]

Depending how much we can cut this down, I may be interested.

I boosted my A3 3.2 and now if we run anything over 20psi, it starts leaking at the gasket. If only I had a metal manifold, I could probably turn the boost up no problem.

This project was Nixed... u can look into the HPA manifold though. i am incorporating this into my build, its only 2k comapred to 4 as in here before the project got abandoned.

[krazyboi]

This project was Nixed... u can look into the HPA manifold though. i am incorporating this into my build, its only 2k comapred to 4 as in here before the project got abandoned.

Yea, that's what I saw. I was recommended to stay away from the SRI b/c it'll affect my torque negatively.

[BOUDAH]

Yea, that's what I saw. I was recommended to stay away from the SRI b/c it'll affect my torque negatively.

didnt u say uw ere turbo?

[krazyboi]

didnt u say uw ere turbo?

That is correct (also, I'm a turbo/car noob so a lot of my knowledge is limited. I try to gather information from random sources and put together what I think is correct).

Sad, I know.

[BOUDAH]

That is correct (also, I'm a turbo/car noob so a lot of my knowledge is limited. I try to gather information from random sources and put together what I think is correct).

Sad, I know.

pmed u

[mars2]

You are true SRI will afect low end torque and spool.
the same rule that happen at 1 atm happen at 2atm or what ever boost.
Alway's remenber that NA is already boosted at 1 atm (14psi or 1 bar)
Your 20 psi is in real 34PSI absolute.
So the same rule for intake manifold if NA or Boosted.

[mars2]

Read All the post from Foffa2002 in that thread:
http://forums.vwvortex.com/showthrea...highlight=show

he is an automotive engineere and have done lot of test.
that's why I want to stay with Oem change over valve on my Supercharger set up.

[mars2]

that summerize it well. it's for VR6 but apply even more fro R32 with changeover valve:

"Boosted or N/A is no difference.
The engine we call N/A work at 15psi .
So if it works well N/A it will work even better at an extra 15psi.


Every really angry turbo motor will produce big nr´s N/A.


So if you dont have to change the OEM VR6 MK3 manifold dont do it.
There is no reason what so ever to spend that cash if you dont go to the next level and get som wild cams and built head and chase power after 7000rpm.

But lots of guys change whatever they can just to be able to have that EIP sticker on the car "

[krazyboi]

mars2, thanks for the info. i'm going to read up on that.

right now, i'm right around 400 awhp and 430 awtp. my engine is fully built and the only limiter now is the intake manifold. it's my daily driver so perhaps the extra power isn't needed. i just like knowing how much power this monster is capable of doing. i figure, if i've put $xxx amount on the car already, why not keep going. it's probably not financially smart at the moment, but it's nice knowing i have a rare car doing crazy things.

[jampy]

Real world resonance port effects

Here is a dyno overlay of the short runners only VS the long runners only (Credit Jeff Atwood)

watchin this results of short runners in solitary,do not understand why everyone thinks in bigs losses of torque with sri in n/a...it is true that lose torque on the beginning but stay up for longer time,and the power gains is substancials,for me in particular it is not importan the torq bettwen 3-3'5k,i'm not go to the supermarket with my r32 and i dont have dayli drive...i think have enought torque for drive on legal roads..

[simple_man]

Some people like to take OEM and improve it across the board
What you referring to with SRI is purpose build to suite the application. It's different view / priority this is why it matters.

I myself run SRI, but I am turbo as per signature. HOWEVER if above mentioned project would succeeded I would paid for this intake. As in mine case it would allow me to spool turbo some 500RPM earlier. This is especially important when in first gear and load is low.

[simple_man]

Some interesting data:



I am keep coming back to this idea of making my own OEM+ intake as well
I know, it will cost heap and I know it will have to be redone number of times to optimise - but it fascinates me

[need_a_VR6]

If torque concerns you it would be cheaper to get a variable turbine turbo working then designing a proper changing manifold.

[simple_man]

If torque concerns you it would be cheaper to get a variable turbine turbo working then designing a proper changing manifold.

I know, in fact I was sizing my space between engine/firewall the other day to see if compound turbo set up will fit there. It's relatively cheaper and high gain.

But still, trying to work out perfect intake system is tempting. I was imagining small OEM size runners that are some 2-3inch longer with addition of secondary high HP resonant chamber and large runners like OEM but with Individual Throttle Bodies, as well as perfect designed resonant chamber that is FEED with air as well.
Almost like two separate intake manifolds, feeding via one main throttle body....

Unfortunately, I am not original here, Porsche used this idea some years back

[need_a_VR6]

That is how the vwms vsr and Schrick vgi work.

Not sure compound is a good idea on gas boost is too low. Holset he351ve might be interesting.

[simple_man]

Some interesting data:

Was digging thru some old data I got on my drive, thought I share.

To add some mud to the water, here is how real life dyno test stack up against theory on above plot. Tested 40mm vs 330mm intake runners. Keep in mind, there is already some 300mm+ in the intake length (valve to the end of oem manifold)



Wonder if trumpets are any good, here is dyno with and without:



Now throw a few more variables to make your day:
- Intake Pipe diameter variation (major impact)
- Intake resonant chamber Volume
- Intake resonant chamber inlet pipe length and how it enters the chamber
- VR6 specific difference in distance to the intake valve and how you deal with it
- Cam profile and timing to capture the pulse wave



Test mule:

[DmcL]

Was digging thru some old data I got on my drive, thought I share.

To add some mud to the water, here is how real life dyno test stack up against theory on above plot. Tested 40mm vs 330mm intake runners. Keep in mind, there is already some 300mm+ in the intake length (valve to the end of oem manifold)

330's and shoehorn in a decent sized turbo that hits full boost around the 5500rom mark on that zetec... lol

[simple_man]

That would create an nice combination! You got intake tuning for max TQ while off-boost. With max assist for a spool and when VE starts to fade away, here comes the turbocharger in it's peak efficiency.
Interesting alternative is to do opposite:
Use short runner tuned for 6000-7000RPM and use turbo that comes on boost early at 3000RPM. That would generate very nice, long and flat torque curve.

All that is just in theory.

[DmcL]

something like this then

http://autospeed.com/cms/title_-Turb...6/article.html

[need_a_VR6]

Your torque will die up top with a turbo sized for quick spool regardless of intake tuning. Exhaust backpressure rules in that equation.

[zippy_109]

Marv,

There is only myself and 1 other confirmed guy that are willing to put up a couple grand each to have these made.. problem is, the estimate from the fab guy is 4k if only making 1. 2 won't drop the price much, if any..

Add one more to your list of willing/paying guy. I have a friend who owns a machine shop who also owes some $$. Let's get this project rolling again!

[PowerDubs]

Meh. The time has passed. I'm on to bigger and better things.

Sorry.

Feel free to carry the torch. I'll watch with interest.

[need_a_VR6]

For anyone carrying it on, I will be willing to hassle you accordingly.

[kevhayward]

Very dropped. I might be working on making an adapter to fit the 3.6 manifold on the 3.2 head. Waiting on a manifold and not hopeful on it being easy, simple or cheap.

Did this ever happen?

[need_a_VR6]

Never got a manifold from the interested party.

[rhcp4life]

Looking into this, looking to build a combo intake and exhaust mani. Started design on intake getting access to a r head next month for dimensions.

[rhcp4life]

I've been doing a bit of design, and looking at different materials. I debated over the idea of going with square, oval, or round runners. In the end i decided on round because of the availability of the tube.

I took some measurements on the intake ports and i thought that i would go with 1.75"id pipe as it has a surface area of 2.4 sq. in. the ports on the head are right around 2.28 sq in.

Here is what the transition flang would look like. It is 1-1/2" thick. that may be a lot of aluminum so if need be i could make a phenolic or carbon to reduce intake temps.

I have a lot of work to go and a lot to learn. I need some direction about runner lengths as well as volume.

[need_a_VR6]

For no resonance chamber 13-14" would be decent for high rpm second pulse tuning. You need much longer to get the first pulse.

Volume is a much funnier thing, I have seen anywhere from .5x displacement to 3x displacement work well. A lot depends on design and throttle body size.

[mldouthi]

I've been doing a bit of design, and looking at different materials. I debated over the idea of going with square, oval, or round runners. In the end i decided on round because of the availability of the tube.

I took some measurements on the intake ports and i thought that i would go with 1.75"id pipe as it has a surface area of 2.4 sq. in. the ports on the head are right around 2.28 sq in.

Here is what the transition flang would look like. It is 1-1/2" thick. that may be a lot of aluminum so if need be i could make a phenolic or carbon to reduce intake temps.

I have a lot of work to go and a lot to learn. I need some direction about runner lengths as well as volume.

Do you have a twist "path" in the loft from square to round? Or is that just how the image can across?

[rhcp4life]

Do you have a twist "path" in the loft from square to round? Or is that just how the image can across?

The software puts that twist in.

[rhcp4life]

For no resonance chamber 13-14" would be decent for high rpm second pulse tuning. You need much longer to get the first pulse.

Volume is a much funnier thing, I have seen anywhere from .5x displacement to 3x displacement work well. A lot depends on design and throttle body size.

How are you calculating the pulses. I'm new to this. How much longer would it need to be for the 1st pulse, assuming that's better.

Also I would probably be using the oem throttle body

[need_a_VR6]

Try this http://www.bgsoflex.com/intakeln.html

Thats the best easy one. There are others like pipeworks or engine simulators.

[mldouthi]

How are you calculating the pulses. I'm new to this. How much longer would it need to be for the 1st pulse, assuming that's better.

Also I would probably be using the oem throttle body

Here is a very crude calculator
http://www.wallaceracing.com/runnertorquecalc.php
and some good info here also.
http://www.team-integra.net/forum/bl...culations.html


What software are you using? I would love to have the bolt pattern and port openings in a cad file to mess around with, I dont own a vr6 but I do enjoy messing around modeling car parts.

[need_a_VR6]

The cross section part of the Wallace calculator seems quite odd... unless it's made for a specific distance from the valve without designating that distance.

[mldouthi]

The cross section part of the Wallace calculator seems quite odd... unless it's made for a specific distance from the valve without designating that distance.

Right, thats why I mentioned its a crude calculator. There are a bunch of factors that arent taken into account on the calculators. But its a starting place.