Z32 Afm Required For 300kw?

[wanted r34gtr]

what was the limiting factor ? was it the afm's or the tuner didn't want to push the injectors above 90% duty cycle

regards

wanted

[Duncan]

unless the tuner mentioned afms or injectors....it probably just stopped making power for the acceptable timing level at the required boost....

[Brandon]

Well he mentioned about restriction on wastegate and dumps but I think thats only part of the problem. The other would probably be the boost controller kit I reckon. With the pfc boost controller kit you cant really tweek much according to him but thats the choice I made by not having any display in the interior.

He mention its running at 90% duty which means its quite safe for now and if I do change injectors, I would be doing a whole lot of other things so maybe I'll just stop here and have suspension and clutch next on the list.

Another thing is the dyno is 4 wheel so maybe all these while the 300kw I had in mind was rwkw and not awkw. And if the boost does hold at 1.2 instead of 1.15, that may well be another 20awkw increase? Anyway I'll leave it for now with that fact that the car is way more responsive and I'm happy with that.

Looking at the dyno results I cant help but notice the initial power was only 220awhp which means its only 165awkw. Thats no where near to the 206 or even 200kw they were advertised for. But if you multiple that by 1.15, that will give you 190awkw. which still isnt as bad.

I'm gonna call Gavin up and see if I can get the Boost graph as well. Will post it up when I get it.

[Brandon]

unless the tuner mentioned afms or injectors....it probably just stopped making power for the acceptable timing level at the required boost....

Yea he tried different timing but could get it to hold and decided to keep it at 1.15 and fine tune it.

[GT-R32]

Still a decent result I reckon. My car only made just under 270awkw in the hands of the previous owner also. But with HKS EVC and of course the 2530s and more boost. There's debate about how much power GTRs lose when comparing all wheel and rear wheel power but I'm sure it makes some difference. My car had stock front pipe, cat and dumps at that time also.

I'm sure it's great to drive now.

[Brandon]

Yea sure is. According to a few it can be between 10-15% drivetrain loss. And of course like you've said more boost = more power. I've seen it rise from stock to where is it now so I dare say it should be another 10-20awkw increase if it can hold the boost.

[R31Nismoid]

I'll break this up… easier

Well he mentioned about restriction on wastegate and dumps but I think thats only part of the problem.

I can tell you without an ouch of doubt, they are not a restriction. My own car, and many many others are proof of this.

Another thing is the dyno is 4 wheel so maybe all these while the 300kw I had in mind was rwkw and not awkw.

No difference really, GTR's are not like a WRX/EVO that runs 50/50 full time 4WD.

Plenty of people have tested and there is bugger all difference between awkw and rwkw in most cases.

Looking at the dyno results I cant help but notice the initial power was only 220awhp which means its only 165awkw. Thats no where near to the 206 or even 200kw they were advertised for. But if you multiple that by 1.15, that will give you 190awkw. which still isnt as bad.

mmm if your initial result is a bit low, perhaps there is a cam timing issue or similar?

Im still dubious of a 15% drivetrain loss though through a stock transfer case, i wish someone would test how much it exactly is

I know modified/beefed transfer cases will lower the result as they lockup much more

[Brandon]

Yea I dont believe its restriction either. More of the boost controller kit's issue (since reading about apexi boost controllers).

Maybe it'll pays running on 2wheel dyno. Only problem is whats involved in running a 33 on 2wheel as I've heard 33 and 34 isnt as easy as pulling the fuse out like 32s.

In any case the 10-15% varies and according to the tuner, what he noticed over the years its about right to assume 10% loss.

I might bring it to Matt Spry if I do get it tuned the next time which I doubt. If injectors are running 90% and I'll be pushing a it more for that little gain, not worth it. And if I decided to buy bigger injectors, the mod disease will hit me again "hmmm bigger injectors hmmm maybe I should get cams afm and run higher power and why waste the bigger injectors running lower duty"... its a never ending process which I dont want it to happen... =x

[GT-R32]

The laws of diminishing returns apply and soon you'll be forking out $20k for a block LOL.

[DAN00H]

I'll break this up… easier

I can tell you without an ouch of doubt, they are not a restriction. My own car, and many many others are proof of this.

No difference really, GTR's are not like a WRX/EVO that runs 50/50 full time 4WD.

Plenty of people have tested and there is bugger all difference between awkw and rwkw in most cases.

mmm if your initial result is a bit low, perhaps there is a cam timing issue or similar?

Im still dubious of a 15% drivetrain loss though through a stock transfer case, i wish someone would test how much it exactly is

I know modified/beefed transfer cases will lower the result as they lockup much more

Agreed, there is no notional % loss applied to otherwise it would be wildly different between std and high power GTR's.

Brendon - what varience in boost levels are you talking abou to pick up an additional 20kw?

[Brandon]

Boost VS Power Graph

And I thought the factory was 0.8bar. lolz. Anyway case closed, until the disease relapse.

[Brandon]

Maybe another 2-4psi? Anyway I agree its all dependant on a whole lot of other factors what I think might not be true as well but for sure it will be higher than what it is now. The question is should I correct it or should I just leave it.

I figured I'll leave it for now.