Max Boost On Gtr Airflowmeters & Pump Gas

[Tabs]

Hi there skyliners

I searched but failed - so hopefully I can get a couple of opinions

I want to run the highest safe boost I can

im pretty sure im being let down by the stock air flow meters and pfc, I have a map sensor and link on is on its was but probably wont put it in for a month or 2 when ill get it tuned

My r32 gtr came with a recent rebuilt forged motor, garret gt35r turbo , tomei cams & gears ,700cc injectors, old power fc tuned by Godzilla motorsport, sard reg , stock intercooler & piping, spitfire coils, and a few other mods, ive recently put a 044 in the tank,

since ive had it ive noticed on boost it blows black smoke (quickly stains up rear bumper heavily) and fouls plugs fairly quickly, I read in a thread when searching for info that you can over tune air flow meters is this true?? maybe this is why im running so rich???

***Ive recently up'd boost to 20psi still running pfc -( which was tuned to 17 psi apparently but I noticed boost controller wasn't plumbed correctly on waste gate & solenoid ) and has stock air flow meters. - would this be suitable for a couple of months or do you recon im push the stock air flow meters to far???

***Secondly once link G4 ecu and map sensor is in what is the max boost you can run on general 98 octane petrol ??? I know the tuner will play a big part in this but whats peoples opinions I was hoping about 30-35 psi??? I don't want to run e85

Cheers and thanks in Advance

Craig

[Tabs]

just found this but still peoples opinions would be choice as!:

This is from Sydneykid

Rule of thumb for Air Flow meters RWKW & Engine BHP

------ ---- OD ---- RWKW ---- RWKW ---- BHP ------ BHP
No of AFM's ---- ------- 1 -------- 2 -------- 1 -------- 2
RB26 ------ 65 ------ 149 ------ 299 ------ 271 ------ 474
RB20/25 --- 80 ------ 226 ------ 453 ------ 376 ------ 683
Z32 ------- 80 ------ 255 ------ 511 ------ 415 ------ 763
Q45 ------- 90 ------ 302 ------ 605 ------ 479 ------ 890

Posted 20 February 2005 - 11:31 AM

[paulr33]

you might be maxing the 5v range of the afm's and if you are, you simply run out of load points

it doesnt cap your power or make the car blow magic smoke

to see if you max the afms monitor, 1 channel, airflow then press next, then press UP

it show you to the score in MV

press RIGHT to clear the top score then drive around and see what top score you get

or better yet

use map tracer and see what load cells its using

monitor

map tracer

press up for ghost trace

press right to clear previous trace

if it runs along row 20 at max load youve run out of load points

you can rescale it using the afm ramp (any tuner can do this) but if you max 5v, you max 5v and nothing can stop that other than bigger AFMs

powerfc faq has all this info

[scotty nm35]

what is the max boost you can run on general 98 octane petrol ??? I know the tuner will play a big part in this but whats peoples opinions I was hoping about 30-35 psi??? I don't want to run e85

Good luck with that... A GT35 won't run 35psi on ethanol let alone 98...

[WMDC35]

/\ maybe 20 22 psi, plus running a few psi over what it's tuned for is asking for it

[Tabs]

interesting

*I thought the garret turbo chargers could handle 30-40 psi easy?? what gives away- shaft? compressor \ exhaust wheels? bearings? seals? or can the turbo handle it just it runs out of efficiency and starts to cook the air???

*I would of thought the ecu would compensate for the extra 3psi and increase the fuel a lil bit and I would get even more power gain if it was tuned for 20 psi?? or could I be starting to lean out ???

*so what I can gather from the 2 comments above reguardless of the ecu \ tune I cant ( shouldn't ) go over 20psi. what you recon the max boost the turbo can handle and the max the fuel is able to handle???

30-35psi I agree was wishful thinking I do have a brand new Garret TO4Z in NZ that I might send over with the link. I have a friend "GTRPWR" running a to4z on 98 pump gas pretty sure he is making 500kw at wheels

Thanks heaps for the feedback scotty, paul and wmdc35 , ill turn down boost right now to 17 ish

[Ben C34]

Just wait the couple of months until your link arrives then use that. Don't kill the engine before it arrives!

[KiwiRS4T]

I have a GT3540R with a .63 ex on my RB30/25 currently making 308AWKW at 22 psi. I have had it up to 28psi but it doesn't make any more power at that level. Someone else's RB30 (might have been an RB30/26) made 350KW at 18psi with the same turbo (.63 GT3540R)

[Tabs]

my stock gtr in nz before rebuild with a mines plug in ecu pods and exhaust on 16psi stock turbos was 291rwkw!!!

from what I can gather for my turbo and pump gas I might as well keep power fc and air flow meters get a GOOD tune for 22psi , would putting my link and to4z make a BIG difference still running on pump gas?? or is the power from 22 psi on my gt35 almost the same if I would run the t04z cause im limited by 98 petrol??

[R31Nismoid]

interesting

*I thought the garret turbo chargers could handle 30-40 psi easy?? what gives away- shaft? compressor \ exhaust wheels? bearings? seals? or can the turbo handle it just it runs out of efficiency and starts to cook the air???

*I would of thought the ecu would compensate for the extra 3psi and increase the fuel a lil bit and I would get even more power gain if it was tuned for 20 psi?? or could I be starting to lean out ???

*so what I can gather from the 2 comments above reguardless of the ecu \ tune I cant ( shouldn't ) go over 20psi. what you recon the max boost the turbo can handle and the max the fuel is able to handle???

30-35psi I agree was wishful thinking I do have a brand new Garret TO4Z in NZ that I might send over with the link. I have a friend "GTRPWR" running a to4z on 98 pump gas pretty sure he is making 500kw at wheels

Thanks heaps for the feedback scotty, paul and wmdc35 , ill turn down boost right now to 17 ish

1. Turbo is simply not capable of airflow @ that pressure and won't MAKE 30-35psi.

2. ECU's do not compensate

3. You should never go over what the car is tuned for, simple.

my stock gtr in nz before rebuild with a mines plug in ecu pods and exhaust on 16psi stock turbos was 291rwkw!!!

from what I can gather for my turbo and pump gas I might as well keep power fc and air flow meters get a GOOD tune for 22psi , would putting my link and to4z make a BIG difference still running on pump gas?? or is the power from 22 psi on my gt35 almost the same if I would run the t04z cause im limited by 98 petrol??

A T04Z is a 400rwkw+ turbo. You have a stock motor... Do the smart thing and leave the GT35 on there before things get out of control and cost you 10k in rebuilding.

The ECU has little to no relevance to the power. So if you are buying a link thinking you'll make more, you couldn't be more wrong.

The T04Z is a larger turbo, so it will make more power on 98 as it doesn't need to run more than 20-22psi to make 400rwkw on 98... Where a GT35 would need 25psi or more to get to 300rwkw and that is basically the limit of the GT35 anyway on 98

GTR stock AFMs run out around 300rwkw. You can "tune past", even to 350rwkw isn't a major problem - but it's not recommended overall as best practice.

And again, it's not a question of BOOST through the AFM - It's about the measuring of the airflow - which is related to boost, but it's simpler to not think of it that way

I'm interested to see how a GT35 is still running stock piping... Can you show a pic of the engine bay?

[Tabs]

I have 2 gtr's in im paraparaum NZ (gun metal grey) after dropping a valve guide that ive spent $15000 on ( and the motor is wrapped up on a engine stand in a lock up next to it havnt put it back in after the rebuild)

ive got my white gtr that I brought a few months ago in brissy that's fully forged and all the work has already been done

my white aussie gtr mods are as follows:

OS Giken twin plate clutch
split fire coil packs
700cc Siemens injectors
044 bosch pump
power FC
turbo smart EBoost 2 controller
oil filter relocation kit
PPG gears in first second and third

block decked, bored out.040" and honed, cp pistons and rings, spool rods, ACL race bearings, R33 GTR crank with long nose oil drive, N1 oil pump, Tomei Sump baffle kit, head decked, valves refaced and lapped, Tomei type B poncams, Tomei adjustable cam gears, cylinder head rear oil return, cometic steel head gasket and exhaust/intake gaskets
Garrett GT35 R turbo, top mount manifold, turbo smart 45mm external waste gate 14 psi spring setup. Greddy intake kit, K&N pod filters, custom intake and dump piping with waste gate plumbed back into exhaust, sard FPR

the best thing is I paid $13k for above gtr

Edited July 17, 2013 by Tabs

[Tabs]

cant load my photos of white gtr error403 ??

Edited July 17, 2013 by Tabs