Jump to content
SAU Community

Recommended Posts

Hi all,

How much power can the stock R34 GT-R air flow meters handle before it needs to be upgraded to bigger afms (Z32's) for more power?

To my understanding, isnt it around 300rwk's and not much more?

Cheers,

they will run to maximum voltage somewhere between 280 and 300kw. From there the tune is "blind", there is only a single point in the ECU for all airflow above 5v which means it is compromised in both fuel and timing to make sure it stays safe.

they will run to maximum voltage somewhere between 280 and 300kw. From there the tune is "blind", there is only a single point in the ECU for all airflow above 5v which means it is compromised in both fuel and timing to make sure it stays safe.

yep

yep

what he means is if its tuned and maxed out at 20psi, if the car overboosts or you turn the boost up the state of tune will not change as the ecu does not know the boost level has changed so it could cause detonation or a too lean of a mixture for the extra boost.

it works the other way as well, if the afm max's out at 17 psi and you tuned the car to 23psi, then you decide to turn the boost down to 17psi, then it will run too rich and you won't be getting the right power / mixtures for that boost level

So its kinda ok but not recomended to tune the car with a maxxed out AFM, if you dont intend on changing the boost at all then you can possibly get away with it if you have a decent boost control that will never fail and overboost

Thanks everyone for all of your replies.

I will be having the following mods:

Garrett GT2860-7 turbos

Apexi Power FC

Apexi Power FC Boost Control Kit (running 1.2, or even 1.3 bar)

Nismo 600cc injectors

Nismo fuel pump

Apexi Power intake kit

HKS cam pulleys

Tomei Poncams 260's type B

HKS Front pipe

HKS Cat

Blitz NuR cat back

So im guessing that with all of the above mods and the boost that I hope to be running (1.2 or even 1.3 bar) I should upgrade afms? I was thinking of the Nismo afms...

Cheers,

yeah I would. and I would get the nismo afms too. I went new gen nissan Z32s on the last GTR, and nismos on this one. performance wise they are very, very close. and the nismos have the advantage of being standard size.

yeah I would. and I would get the nismo afms too. I went new gen nissan Z32s on the last GTR, and nismos on this one. performance wise they are very, very close. and the nismos have the advantage of being standard size.

Oh ok so the Z32's are actually bigger than my stock ones? Which means they wouldnt bolt straight up?

And the Nismo ones would use the same ECU plugins?

Also, you dont think its over kill to get the Nismo ones for my application with the mods I have listed above?

Cheers,

Edited by xanavinismo

For 1.2-1.3 bar, i wouldnt bother upgrading until you actually know you've maxed them. I think its undue spending at this point.

You might well find you might come close, but they wont actually max @ that boost level. Every setup is different of course

And ye, if you do max them - Nismo all the way. Z32's are too much of a stuff around.

www.perfectrun.com.au are the cheapest for Nismo's that i've found recently... they can get em cheaper than an importer i know :D

Perfect run (providing stock) should have em here in 2-3 weeks so its not as if you have to wait forever anyhow.

What about Power FC D Jetro Glen? Then you wont have to run air flow metres at all. Just unplug them.

Thats how mine is with my Vipec ECU

Hi Bakes, unfortunately I already have my normal Power FC installed so its too late for D Jetro?

Oh and R31Nismoid, thanks for your input. I am most likely heading towards that direction where I get the car tuned and see if they do actually max out cos then I can always replace them with the Nismo ones if necessary.

On a bit of a side note, should I also upgrade the fuel pressure regulator to handle the Nismo 600cc injectors & Nismo fuel pump along with the other mods I have?

I am thinking of the Nismo adjustable fuel pressure regulator...

Cheers,

Cheers,

Edited by xanavinismo

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Mate you saved be from dying in the Perth summer. AC wasn't changing direction and just going into diagnostics mode fixed it. You're a legend and I would shout you a beer if I could!
    • Unfortunately effort gone to waste, you will have substantial issues with how the manifold and wastegate have been integrated. You would be so much better off with a modified stock manifold like this: https://hypergearturbos.com/product/rb25detexgatedmanifold/   OR literally just getting a off the shelf Sinco or 6Boost manifold as myself and others have mentioned.  
    • Yuck. But it's kinda the same principle, moving timing around to make car run bad but sound good.... I went for a more spirited tuning drive to iron out a few things. Car no longer stalls, and it loved to dip RPM low when you clutch in. After tuning this (and the 4-5 tables that HPTuners/LS1 OEM ECU wants for idle air correction) it's now behaving somewhat normal. All expected because there's a new TB, new Intake manifold and that new TB which is 102mm vs 78... has an entirely different IAC passage which is smaller because ????? Unfortunately at this point I went to make further fine tuning changes to avoid it flaring up, you know... _tuning_ the HPTuners dongle died. Well to be more accurate - The USB cable died in a fashion that anyone who has ever charged a phone will recognize. After the app demanding I resync it 50 or so times (which all 'succeeded' but all failed) the device does not want to sync and I've logged a ticket with support to see if it's fixable. US Support said it was a 'storage issue' but after removing the SD card inside it and formatting it/fixing it the issue does persist. Unfortunately usually the fix is "Turn in your old dongle and pay $700 for the upgraded one" it's cheaper because I get some free licence credits I unfortunately don't need. However I'm 10 minutes down the road from HP Tuners AUS/VCM so at least I won't need to post it, and logged a new ticket for support over here. Definitely drives different. My SOTP dyno believes it's probably making 310-320kw instead of the 280 before.  It scrambles for traction a little now whereas it previously different. It drives like a bigger cam car up top even though the cam is smaller, likely due to the cam not being advanced 6 degrees. The timing is deliberately low and the fuel is very rich so who knows if this will improve on the dyno. It may, imperceptably. Also funny is removing the pineapples definitely makes the car squat more and axle tramp less. So this behavior of having more top end, squatting more, and scrabbling for traction more makes me think = more power. But I could have just been sitting on the threshold of that kind of behavior before. Time will tell if my butt dyno is calibrated right. I need the exhaust leaks fixed before dyno tune for obvious AFR related reasons - I repositioned the pipes but I'm not confident it's fully sealed even if it is better. At least the car does drive around while I cannot tweak/tune it for now. And I have aircon again. medium success!
    • Don't use that manifold. Please don't use that manifold. Sunk cost fallacy is not worth the later pain. None of these will be relevant to the change that will come from the different turbo and manifold. As in, the effect of the exhaust will be nil, regardless of what else is changed. And all the cam and fuel system stuff is not changing either way, so has no effect. The turbo and manifold (and to a small extent the wastegate)....big change.
×
×
  • Create New...