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Hi guys have just tuned my car at a very reputable tuner I’n sydney and it made 269rwkw on 20psi mods- hks gtss turbos,tomei manifold , xforce dumps, hks front pipe, Apexi cat, nismo exhaust, walbro460, 800cc injectors, Hks fuel rail,haltech platinum pro, wide band,g reddy hard pipping kit stock cooler car was rebuilt forged pistons etc less than 7000kms ago now the issue I have is this Gtr should be putting out 330kw in that range I have taken short on this build and am completely and utterly shocked can anyone shed some light here this is a brand new build 

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Cam gears will help dramatically, put a decent cat in it, check the exhaust for restrictors, check the ignition logs on the haltech for scatter. 
 

ive also seen quite a few r33s that made no power cause you couldn’t put any ignition advance in them due to faulty crank angle sensors

Sorry has tomei cam gears 

2 minutes ago, r32-25t said:

Cam gears will help dramatically, put a decent cat in it, check the exhaust for restrictors, check the ignition logs on the haltech for scatter. 
 

ive also seen quite a few r33s that made no power cause you couldn’t put any ignition advance in them due to faulty crank angle sensors

Has tomei cam gears, crank angle sensor is new 

4 hours ago, KiwiRS4T said:

What did the tuner say ?

How big is the cat?

How big is the exhaust at its narrowest (typically at he rear muffler)?

Tuner said power was strong until 5000rpm then ran it flattened out all of a sudden he mentioned the cooler, I still have a stock one I’m gonna change that now I think. Also cat is 80mm narrowest point on muffler I’ll have to double check that

Something is wrong but its not the intercooler.    I have a stock r32 rb26 making 245rwkw on e85(12psi).  And an rb26 with single turbo making 520rwkw(26psi) with the stock r32 gtr intercooler.

 

I would be doing check for boost leaks, rag in the intercooler piping, timing off , timing belt off and compression on motor. 

Even on pump fuel 20psi with those turbos should be a lot more.  

Oh and double check you actually have gt-ss turbo's :)

 

I'd also consider another tuner, specially if he offered to sell you an intercooler :) 

Edited by Butters
  • Like 1
1 hour ago, Butters said:

Something is wrong but its not the intercooler.    I have a stock r32 rb26 making 245rwkw on e85(12psi).  And an rb26 with single turbo making 520rwkw(26psi) with the stock r32 gtr intercooler.

 

I would be doing check for boost leaks, rag in the intercooler piping, timing off , timing belt off and compression on motor. 

Even on pump fuel 20psi with those turbos should be a lot more.  

Oh and double check you actually have gt-ss turbo's :)

 

I'd also consider another tuner, specially if he offered to sell you an intercooler :) 

Yeah I’m gonna do a complete check of cooler pipping flow is being chocked off more I think of it can’t be the cooler it might be a possible a rag or something is stuck or my cat may have a blockage. The tuner did the timing checks, They are 100% gt ss turbos 

3 hours ago, BK said:

I have told the tuner to drop of the cat they have just told me it flows much better, they think cat is fine. They didn’t chuck it on the dyno yet, im taking the punt and ordered a de-cat and will be doing a power a run with it and see what I get it atleast rule that out hopefully it’s the cat. They checked the exhaust from the cat back said there was no restrictions in it anywhere either.

Did you read my post from 10 years ago ? Unless you have run it on the dyno with just the front pipe any visual inspections of it being ok are purely just speculation. My cat "looked" ok. Run car on dyno and barely made any power as mentioned. Mid range was pathetic compared to what it should have been.

We then jumped straight under the car, unbolted the exhaust at the front pipe and let the cat back just hang there under the car, so the exhaust was purely just the manifolds, turbos, dump pipes the into front y pipe. Run it without touching anything and car went straight back up power. It was 360ish kw from 250ish kw, but Remember the exhaust was completely open. Sounded awesome. The build to boost was also affected by the blocked cat, making the car build boost really, really slowly. Your boost curve looks very slow to build, which it also pointing to excessive backpressure. I dont think your problem is as bad as what mine was. With no restriction the turbo should go from 0 - 20psi in around 1000rpm - 1500rpm when nailed. Power range depending on dyno type with 98ron at 22psi should be anywhere between 290 - 350kw with a full exhaust fitted. I've noticed around 310 - 330kw generally on different dynos. Max boost efficiency is 1.6bar for GT-SS / -9 turbos so about 23-24 psi.

You better hope its your cat causing it or you have way bigger problems somewhere else to worry about.

 

36 minutes ago, BK said:

Did you read my post from 10 years ago ? Unless you have run it on the dyno with just the front pipe any visual inspections of it being ok are purely just speculation. My cat "looked" ok. Run car on dyno and barely made any power as mentioned. Mid range was pathetic compared to what it should have been.

We then jumped straight under the car, unbolted the exhaust at the front pipe and let the cat back just hang there under the car, so the exhaust was purely just the manifolds, turbos, dump pipes the into front y pipe. Run it without touching anything and car went straight back up power. It was 360ish kw from 250ish kw, but Remember the exhaust was completely open. Sounded awesome. The build to boost was also affected by the blocked cat, making the car build boost really, really slowly. Your boost curve looks very slow to build, which it also pointing to excessive backpressure. I dont think your problem is as bad as what mine was. With no restriction the turbo should go from 0 - 20psi in around 1000rpm - 1500rpm when nailed. Power range depending on dyno type with 98ron at 22psi should be anywhere between 290 - 350kw with a full exhaust fitted. I've noticed around 310 - 330kw generally on different dynos. Max boost efficiency is 1.6bar for GT-SS / -9 turbos so about 23-24 psi.

You better hope its your cat causing it or you have way bigger problems somewhere else to worry about.

 

Hey mate yes I read your post, I agree with what your saying the tuner wants to triple charge me on off the Dyno etc.So it hasn’t been the easiest thing to deal with. I am gonna delete the cat and have a straight through de cat I should see a big change With a de cat on the Dyno. If it’s not that then I do have big problem and I’ll be taking the car back and probably start looking at the cooler next 

2 hours ago, Dose Pipe Sutututu said:

Might as well run a stock cat, probably flows as much as that Apexi over priced haram cat lol

 

I don't know what cat he's running but the current 80mm Apexi super cats are 130cpi which is awesome.

They are also $1200 - $1400....

ouch.

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