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RB25DET forward facing plenum


LerchR33
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Just looking to see some feedback and opinions on changing from a stock intake to a forward facing style.

It seems like a fairly pricey thing to change and would take some labour and adjustments under the hood.

It seems very logical to run a forward facing plenum for many reasons. I would like to know what effect you felt it had on your car.

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Look 100x better, 100000x easier to change/upgrade injectors, easier to change spark plugs... little bit of stuffing around to convert but nothing major. Much shorter inlet path.

Would be interesting to see if someone has done a back to back comparison on a near stock motor with no changes other then the intake... When I did it I changed injectors and turbo at the same time so cant really compare

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Look 100x better, 100000x easier to change/upgrade injectors, easier to change spark plugs... little bit of stuffing around to convert but nothing major. Much shorter inlet path.

Would be interesting to see if someone has done a back to back comparison on a near stock motor with no changes other then the intake... When I did it I changed injectors and turbo at the same time so cant really compare


I asked for back to back results on the same tune a few years ago. From memory someone did post results and they were in line with what everyone else says. The theory and results behind the plenum is almost the same as na, which is surprising.

Yeah they look good and you can clean up all wiring and coolant and fuel lines to fit below it. But it's still around $400 for a useless thing.
Have around $400 spare and want something to do? Go for it
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I have talked myself out of non standard RB25 manifolds and plenum chambers so many times it isn't funny .

Just yesterday I was looking at a pretty blue Freddy going onto a GTS25T and asked again the shop owner does this cost torque and drivability right where cars are driven most of the time .  Quick answer , yep more top end but costs down low . 

It is also very obvious that things like the thermostats housing and oil filter are considerably harder to get at . No crossover pipe but that's not real hard to remove once you've done it once or twice .

I think the reality is that the J pipe or whatever is the way to go or if being real stealthy you're stuck with return flow type intercoolers .

The factory alternatives are the RB26 setup or the Y pipe and plenum like some R34 RB20/25 DEs use .   

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I've got one on my motor,why? For bonnet clearance when my 25 was in my 180, now I still have it on my 32 as bonnet clearance with an rb30 and because top feed standard hight injectors.
More top end? Barly noticeable at 300kw, however there was a noticeable loss of low-end/midrange power on the rb25 can't comment on the difference with the 30 thou

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i have back to backs with 320rwkw greddy and plazmaman vs std and in both cases there was very little difference and there was zero difference between std throttle and q45 on the greddy at 350rwkw.

That said the extra accessibility was worth it on both cars as they see lots of track work.

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I have talked myself out of non standard RB25 manifolds and plenum chambers so many times it isn't funny .

Just yesterday I was looking at a pretty blue Freddy going onto a GTS25T and asked again the shop owner does this cost torque and drivability right where cars are driven most of the time .  Quick answer , yep more top end but costs down low . 

It is also very obvious that things like the thermostats housing and oil filter are considerably harder to get at . No crossover pipe but that's not real hard to remove once you've done it once or twice .

I think the reality is that the J pipe or whatever is the way to go or if being real stealthy you're stuck with return flow type intercoolers .

The factory alternatives are the RB26 setup or the Y pipe and plenum like some R34 RB20/25 DEs use .   

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I have talked myself out of non standard RB25 manifolds and plenum chambers so many times it isn't funny .
Just yesterday I was looking at a pretty blue Freddy going onto a GTS25T and asked again the shop owner does this cost torque and drivability right where cars are driven most of the time .  Quick answer , yep more top end but costs down low . 
It is also very obvious that things like the thermostats housing and oil filter are considerably harder to get at . No crossover pipe but that's not real hard to remove once you've done it once or twice .
I think the reality is that the J pipe or whatever is the way to go or if being real stealthy you're stuck with return flow type intercoolers .
The factory alternatives are the RB26 setup or the Y pipe and plenum like some R34 RB20/25 DEs use .   

I have talked myself out of non standard RB25 manifolds and plenum chambers so many times it isn't funny .
Just yesterday I was looking at a pretty blue Freddy going onto a GTS25T and asked again the shop owner does this cost torque and drivability right where cars are driven most of the time .  Quick answer , yep more top end but costs down low . 
It is also very obvious that things like the thermostats housing and oil filter are considerably harder to get at . No crossover pipe but that's not real hard to remove once you've done it once or twice .
I think the reality is that the J pipe or whatever is the way to go or if being real stealthy you're stuck with return flow type intercoolers .
The factory alternatives are the RB26 setup or the Y pipe and plenum like some R34 RB20/25 DEs use .   


Groundhog day?

I've never regretted mine, but it was part payment for some wheels. Car has always driven fine
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