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I'm pretty well at where I want to be modswise with my car now and I'm wondering what I should go for next without taking the plunge on a new turbo. I've been told that there's a LOT of power being thrown away by the stock plenum. If so how much are we looking at here. Someone told me a 5-6L replacement would really help. Now since I know nothing about plenums I don't know whether or not this is true at all. It would help feed the cylinders better right?

These are my current mods (or I at least have the parts and I'm about to fit / tune them if I get off my arse)

FMIC

13psi (needle valve)

SAFC

HKS Adjustable CAM gear

Trust Airinx pod w/ cold air partition

Twin 3.5" catback + 1 piece HPC coated dump/front pipe with separate wastegate line.

Not sure of power yet, but I'm assuming it'll be between 170rwkw and 180rwkw once I get it all tuned.

Does anyone know if a new plenum would benefit me or would I be throwing away money.

Cheers,

Michael

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Thanks. I guess the guy I was talking to had nfi then. There must be some other way to get more power without going to a new turbo. I just bought the SAFC so ignition timing is out of the question for me. Are there any other bolt ons I've forgotten to bolt on?

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Originally posted by MIC33R

I'm pretty well at where I want to be modswise with my car now and I'm wondering what I should go for next without taking the plunge on a new turbo. I've been told that there's a LOT of power being thrown away by the stock plenum. If so how much are we looking at here. Someone told me a 5-6L replacement would really help. Now since I know nothing about plenums I don't know whether or not this is true at all. It would help feed the cylinders better right?

These are my current mods (or I at least have the parts and I'm about to fit / tune them if I get off my arse)

FMIC

13psi (needle valve)

SAFC

HKS Adjustable CAM gear

Trust Airinx pod w/ cold air partition

Twin 3.5" catback + 1 piece HPC coated dump/front pipe with separate wastegate line.

Not sure of power yet, but I'm assuming it'll be between 170rwkw and 180rwkw once I get it all tuned.

Does anyone know if a new plenum would benefit me or would I be throwing away money.

Cheers,

Michael

Here in Sweden it麓s my next step... every one tells me to make a new plenium, its really doing alot, says my friend.

However, i am really onshour how to built it, has in SDU seen pics of many diffrent plenium, round, originalstyle but the over part is round and some one ho is using gtr plenium on a gts-tR33 and so on....

Now i cant make up my mind?!?? whitch style does i schose??! or is it: all exept original is god!?!

Regards Klas

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Hey mic: how much does a custom plenum cost????

It seems that it would be KINDA beneficial..

cuz like when u look at the stock inlet plenum..umm the 1st and 6th cylinders must be missing out some of the inlet air??

what u reckon??

oh and when people get custom ones..the inlet becomes umm how can i describe it...kinda like the SR20 inlet right??

so how do they ensure that each cylinder is gettin an even feed..

cuz u know the SR20 inlet feeds from the front..

mc

ps : have u ever heard of a Carbon Fibre plenum?

:shake:

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SkylineMannen:

I really have no idea. Sorry :). I'm not really much good with the design of parts, but I'd suggest copying one of the big brands.

Marcus:

I've seen them go for between $700 and $4000. There's a lot out there.

With regards to the cylinders, I agree that 1 and 6 would not be fed as well as the others, but I'm not so sure how much it would make a difference with an engine like mine. ie not heavily tuned, so the inner cylinders would not be sucking all the air. (Please remember I am not an engine guru)

I think with a front feed would be better for the intercooler piping, but the back cylinder would have to miss out on a bit of the air. I'm not sure though, so this is probably best left to the experts. We are talking turbo cars here, so it is compressed air, which would have to help feed them all.

Re Carbon Fibre - no idea. It'd look sweet though :)

Cheers,

Michael

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MIC33R, thanks for your reply.. =) it still bother me whit the same thing, dont the six cylinder miss air?! but still it is comp, air so i dont think it麓s matters at all!?! if u have the intercooler piping in front.

Turbo gurus over here says prox, the same thing, but think if they are wrong??? reply on that shuld be disaster for the job u put down to build a plenium, but still maybe whort it??!

Regards from the Cold Sweden.... Polar bears on the street below =))

//Klas

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as said before unless u r running like 250kw+@rw new plenum aint goona help much. In Serious Performance 6 mick from sub zero said that along the line that for ever 1 psi of boost u should get 7kw@wheels but with the stock intake they were getting 3-4kw@wheels.

Mayb talk to them about intakes!:)

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FYI - I've still got the standard intake plenum on my car and am making easily in excess of 300rwkw.

Don't waste $1000 (minimum) on a mod like that, when $1000 could be much better spent on other mods.

matt

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Originally posted by INASNT

as said before unless u r running like 250kw+@rw new plenum aint goona help much. In Serious Performance 6 mick from sub zero said that along the line that for ever 1 psi of boost u should get 7kw@wheels but with the stock intake they were getting 3-4kw@wheels.  

Mayb talk to them about intakes!:)

Do u have any url麓s or mail adds to those dudes?! its a really good subjekt to talk about =))

//Klas

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Guest nismogtsx

Hey i went the custom plenium and it was a huge deal.

I had 177rwkw before and could only run 15psi due to heat

issues. The cast iron original piece heats allot....

But now with the custom side flowing plenium the heat

is minimised and at 15psi i now make 213rwkw...

For $900 thats pretty good....

It has also allowed me to be more confident with my boost

and have run 17psi to achieve 224rwkw.... (Using Dry Ice i

will admit)

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