Inlet Manifolds

[ISL33P]

understandably why, but have a look at the vl turbo world and they dont give two hoots...they do get plenty of canary's, but dont give cops reason to pull you over and they wont...

[wolverine]

I would take you up Ariel but I am sitting on a tired RB25 which I gathered doesn't fit the bill for you.

[ISL33P]

As long as there is plenty of turbo flow and everything else to back it up, more than happy to consider it. If you like, pm me the details of the engine mod's and we can go from there.

I want to get results at different boost levels to see the overall impact. I also have an egt kit I would like to install to get even more data to back things up one way or another.

[RBceffy25]

Has anyone ever noticed the rib-like castings on the inside of the standard GTR log plenum?

I'll get some pics up.

[bubba]

Yeah I did notice them when I made my custom plenum, as they are spiral-like I figured they were to help distribute air to each runner..

[r33_racer]

Lol funny you should mention that, I just pulled one apart an hour ago. First time I noticed them too. I figured much the same; an attempt to direct air towards the runners rather then letting it all gush straight to number 6. I would have thought they would need to be abit longer (protrude in more) to have enough of a difference.

[ISL33P]

exactly the reason why they have done it. there are some cad simulation programs results which show this would be beneficial.

as for all the air being directed to no6....this is not necessarily true considering cylinders fire at different times and the air is used only when valves are open. you will find that the rear cylinders, 5 & 6, of the gtr plenum actually flows less than the 1 & 2.

[TurboX]

You could always build your own like I did for $1200 - for LOOKS!

[dori34]

dammit ariel, why couldn't you offer this free RB25 plenum 2 months ago

[ISL33P]

hahaha yeah sorry

[Lukas 33]

Have you got any CFD analysis videos of the plenums?

[ISL33P]

Do you have access to the prograns to do the CFD analysis?

[Lukas 33]

Do you have access to the prograns to do the CFD analysis?

Yeh I have access to solidworks CFD fluid analysis

[ISL33P]

Oh good. The reason why i asked is becasue sometimes people just ask it because they think its fancy and have read it somewhere else....and I also wanted to see who could do it for me so I could compare it to flowbench figures...unfortunately your in QLD.

So that would answer your questions, no I don't but would like to find somene local who could do it for me and show me how its done...so if there is anyone out there who can, please pm me.

[r33_racer]

Interesting about the flow. I thought the major belief was that 5 and 6 flowed abit more (or atleast received air first and more of it) and so always ran a fraction leaner as a result, hence why alot of tuning shops richen 6 up by 1.5% and 5 by 1% or something like that.

Funnily enough I thought all forward facing plenums were susceptible to that problem by that same reasoning.

Did you test this by egts on each exhaust runner with matched injectors? or some kind of flow test on the manifold itself?

[ISL33P]

that is far from the truth!!!! another one of those internet created misconceptions....and there are plenty more out there

this was tested on a flow bench....EGT testing is coming with the test car

[toddlls]

Any for RB20DET on a R32Gtst?

[Lukas 33]

Do you have any 3d CAD drawings of the plenums?

If you have 3d CAD drawing then performing CFD analysis on it shouldnt be too hard

[Rolls]

how accurate is solidworks for cfd analysis?

it is generally pretty good for everything else, never heard any reports on the flow stuff though.

Edited November 1, 2010 by Rolls

[ISL33P]

as for rb20 info, watch this space when i get some time after the rb25 testing

i actually need someone to draw them up for me to do the cfd

from reports cfd results are actually very similar to flow test results when the same environment is used, meaning real world vs what is simulated

Edited November 1, 2010 by ISL33P