anybody wanted to design there own plenum chamber intake

[Davezj]

Have a look at this thread it is from the Z car forum and this guy goes to town over developing his own plenum, which is all CFD test prior to fabrication.

it is a 20 page monster thead but worth reading for all the info on flow dynamics and design.
http://forums.hybridz.org/topic/6154...-plenum/page-1

http://forum.9000rpm.co.za/viewtopic.php?id=6712

[fassi1]

Great search Dave

[Davezj]

This is a link to inlet manifold trumpet/velocity stack design

http://www.clubvr4.com/forum/showthr...y-stack-design

[fassi1]

Is it something you are considering Dave to get custome made?

[Davezj]

i am thinking about it.
but i am considering making it myself from PVC platic sheet and pipe.
i just don't know if it will hold the pressure or blow apart.
but as i say, i am only considering it at the moment.
why am i considering it, just because.

[fassi1]

Always worth trying but I'm not so sure about PVC or any plastic.

[Davezj]

i have been playing with PVC and vigerous boiling water will soften it enough to bendit and mold it but only just, so that is 100 Deg C

i did some thermal measurements on the inlet plenum where it joins the inlet manifold and that joint got to about 70 deg C. So i am thinking it will be OK.

[scott.mohekey]

I'm planning on doing something like this with dual barrel independent roller throttle bodies on the 3uz-fe that's going into my Supra.

[Davezj]

i just think it is daft that the plenum goes right back over the rear rocker cover.
again from what i have been reading in an N/A engine runner length makes a big difference to the torque prduced and where it comes in, in the rev range.
so an actively adjustable runner length is the way to go with N/A engines, to move the torque up the rev range as the rpm climb. sort to start with then long mid revs and short at high revs.
But in a forced induction turbo engine i don't believe it makes that much difference what the runner length is so shorter seems better, the engine is very torquey low down in the rev range anyway so if it does make a difference then more torque high in the rev range will be ok by me.

but as i say it just theory for now.

[scott.mohekey]

The shorter the runners, the higher in the rpm range the peak torque is realised. It's obvious from the size of the turbos, the tuning of the runner lengths etc that this car was designed to have good low down power.

[Davezj]

yes it is, but as i said, pushing some of this torque higher up the rev range with sorter running will not be a bad thing. but as it is forced induction, i don't think it will have that much effect

the current design of plenum and runners on the VR4 do not have any kind of bell mouth inlet on it so the current design is ineffecient at moving the air down the runners to the inlet manifold.

[vr4cobra]

I am starting to look into customizing my spare Plenum. Was actually hoping someone has tried it to know if it beneficial to our cars or not. And if there would be any wiring, hoses or even throttle cable will require modifying to fit the throttle body in its new location apart from the obvious IC piping will need to be modified.

I was actually thinking cutting tubes half length and welding a 3" chamber to it, either that or going custom stainless one.

Has anyone on here actually done this before?