Modifications To R32 Gtr Airbox

[Brezza]

hey guys,

my mods are the following:

fully rebuilt RB26 with forged internals

recond head (done when engine rebuilt)

R34 GTR intercooler

Mines dump pipes & Trust y pipe

3in Decat

3in cat back exhaust

3.5in muffler

660cc injectors

Walbro Fuel pump

Nistune ECU

Garrett -5' turbos

stock AFM's & Airbox

Bleed Valve set to 18psi

last dyno run around 6 month ago 320rwkw & 18psi on 98 octane

New Parts to come

Turbosmart e-boost street

Yellow Jacket coilpacks

Nismo AFM's

i am wanting to safely have a tune over that 320rwkw without having the AFM's maxed out

will i need to install pods or modify my stock 32 GTR airbox to push the boost up to 20psi or more and try for 350rwkw.

i heard that the R34 GTR airbox will flow 350rwkw, but will the stock R32 GTR one do the same?

will 350rwkw be achievable with the mods i have without having to change anything else?

also i am running 100 octane fuel now, and will be getting the tune done for that fuel.

[Deano 1]

the stock airbox should flow 380-400kw ive seen a fair few people on here say that they have done it. You should see 350 with them mods and the AFM's. 320kw for the factory afms is pritty up there, but than again could be a happy dyno.

anyway let us no how you go, as thats the same setup as i plan on running once i built my motor.

[archie01]

will 350rwkw be achievable with the mods i have without having to change anything else?

Yes. I ran close to 380rwkw with a standard 32 gtr air box. Remove the front intake snorkel that goes to the headlight if it's still there. Standard air filter.

[Brezza]

Yes. I ran close to 380rwkw with a standard 32 gtr air box. Remove the front intake snorkel that goes to the headlight if it's still there. Standard air filter.

yeah,

i still got that front intake snorkel.

i'll get the mechanic to remove it when he changes the AFM's

its good to know that the stock air box can still flow enough to get close to 380rwkw. i'd pefer to keep the GTR looking stock under the hood.

cheers mate

[R31Nismoid]

I highly doubt you'll get a legit 320rwkw out of stock AFM's. You'll be tuning past thier limit for that level.

Stock AFM's limit is around 280-300rwkw, anything more and it's being tuned past...

Given you have -5s which are 380rwkw-400rwkw (20-22psi) of turbo, you need AFM's.

[Brezza]

I highly doubt you'll get a legit 320rwkw out of stock AFM's. You'll be tuning past thier limit for that level.

Stock AFM's limit is around 280-300rwkw, anything more and it's being tuned past...

Given you have -5s which are 380rwkw-400rwkw (20-22psi) of turbo, you need AFM's.

yeah the tuner did say that he tuned past them.

i'm really wanting to get the turbo's really coming alive at around 20-22psi

the jump from 15psi to 18psi was huge on those turbo's it seems the high boost is needed to really wake them up.

R31Nismoid, do you think that the airbox would be able to flow 350rwkw?

i am saying that number because of the intercooler and suggested exhaust would possibly be holding me back from more.

[R31Nismoid]

Considering Archie made 380rwkw, i would imagine you'd easily make 350 if you do what he said.

[Deano 1]

i was reading another thread today that i found in search.... and there was a guy on there saying his making 340kw with the stock box in place. so its been done mate. you should have no worries

[george_afc_23]

Hey guys,

Pretty new to all this but I was reading in HPI magazine about tuning gtr's...they suggest the -5 turbos, nismo fuel pump and 660 or 700cc injectors as mods that will suit eachother capable for around 300rwkw mark...didnt mention anythin about changin afm's?....at what power should you look at changing them? I've also heard while it's illegal that some just gut their afm's for better performance, anyone heard of this?

Thanks, George

[GTRPowa]

Hey guys,

Pretty new to all this but I was reading in HPI magazine about tuning gtr's...they suggest the -5 turbos, nismo fuel pump and 660 or 700cc injectors as mods that will suit eachother capable for around 300rwkw mark...didnt mention anythin about changin afm's?....at what power should you look at changing them? I've also heard while it's illegal that some just gut their afm's for better performance, anyone heard of this?

Thanks, George

Sup,

As far as I know you can only generally gut an AFM if you are running an engine computer which uses a MAP sensor.

These people would for example, be running a powerfc d-jetro (which uses a MAP sensor) and then gut their AFM's for the 'extra' airflow.

This would be to retain a stock air filter setup, whether factory airbox, or the huge range of pods, without going to the cost of buying/making a pipe to replace them.

[R31Nismoid]

Hey guys,

Pretty new to all this but I was reading in HPI magazine about tuning gtr's...they suggest the -5 turbos, nismo fuel pump and 660 or 700cc injectors as mods that will suit eachother capable for around 300rwkw mark...didnt mention anythin about changin afm's?....at what power should you look at changing them? I've also heard while it's illegal that some just gut their afm's for better performance, anyone heard of this?

Thanks, George

They are the WRONG turbos for 300-330rwkw.

Please do a search, there is plenty of info around, hell there is an entire thread devoted just to "-9s & -5's".

[XRATED]

yeah the tuner did say that he tuned past them.

i'm really wanting to get the turbo's really coming alive at around 20-22psi

the jump from 15psi to 18psi was huge on those turbo's it seems the high boost is needed to really wake them up.

R31Nismoid, do you think that the airbox would be able to flow 350rwkw?

i am saying that number because of the intercooler and suggested exhaust would possibly be holding me back from more.

Honestly your pushing the upper limmits of a stock 34 cooler, 3" exhaust and a stock airbox anything close to 350rwkw... It can be done, but your not doing yourself any favors by not addressing them. The cooler will flow allright at 350, it will get heatsoaked fairly quickly through. There is a huge difference between 3" exhausts, just make shure you have a decent y pipe (the merge from the two dump pipes to the cat) as the factory set up is junk.

I'd keep the snorkel and modify the air box. Cut a hole in the airbox before the filter and run a hose from the front bar/guard into the box- it's been done plenty of times before... search 'cold air induction'.

As for you AFM's, rb20afm's plug directly into the rb26 loom and are good for 200rwkw each. They're also bigger than the 26 afm's. But if direct fittment and stock look are the goals, then the extra bucks for the nismo's are worth it.

Hey guys,

Pretty new to all this but I was reading in HPI magazine about tuning gtr's...they suggest the -5 turbos, nismo fuel pump and 660 or 700cc injectors as mods that will suit eachother capable for around 300rwkw mark...didnt mention anythin about changin afm's?....at what power should you look at changing them? I've also heard while it's illegal that some just gut their afm's for better performance, anyone heard of this?

Thanks, George

Keep reading... and not just HPI.

[Brezza]

Honestly your pushing the upper limmits of a stock 34 cooler, 3" exhaust and a stock airbox anything close to 350rwkw... It can be done, but your not doing yourself any favors by not addressing them. The cooler will flow allright at 350, it will get heatsoaked fairly quickly through. There is a huge difference between 3" exhausts, just make shure you have a decent y pipe (the merge from the two dump pipes to the cat) as the factory set up is junk.

I'd keep the snorkel and modify the air box. Cut a hole in the airbox before the filter and run a hose from the front bar/guard into the box- it's been done plenty of times before... search 'cold air induction'.

As for you AFM's, rb20afm's plug directly into the rb26 loom and are good for 200rwkw each. They're also bigger than the 26 afm's. But if direct fittment and stock look are the goals, then the extra bucks for the nismo's are worth it.

i have one of those off the shelf y pipes, i am not sure what brand it was. but it was one from car toys. the previous owner put it on there before i bought the car. the 3in cat back is pretty much all straight pipe with 2 mild bends to the 3.5in oval muffler.

i did look into getting 2x RB20 afm's but considering that they're just as old as my stock ones and they're from different cars they may not read evenly and maybe be a little harder to tune perfectly.

i opted for the nismo ones for the obvious that they're an upgrade, brand new & look stock.

my missus car has leaned out and overheated making one piston crack, this is all due to the AFM. its a WRX btw. so i just didnt want my car doing the same because i was getting my car tuned past the AFM limit and given they're over 20 years old.

[Brezza]

just an update,

the tuner called me and said the car made 351rwkw on 21psi

i am picking up the car tomorrow and i'll post up a dyno graph of the results.

i am not sure yet whether the snorkel was removed.