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hi all,,

just baught a gt3076 from gcg cost me 2750 including dumppipe. i told my mechanic i wanted around 275-290 rwkw.so he asked gcg and they said yep we got the turbo for you. they sent it out, hooked it up tuned it and only made 247rwkw, i said thats not good enough, sent it back to them were they made it to these specs: compressor inlet 59mm, 60trim compressor, turbine 56.5 exducer,76trim tubine wheel. with a inlet a/r .60 my tuner reckons that its being restricted by the a/r .60 and should be .70 on the inlet. but gcg and my mechanic reckon its my car and not the turbo holding it back.

So would anyone have any ideas as to what it could be otherthan the turbo itself thats stopping it from making decent power?. it made 348 rwhp, around 255 rwkw?, at 17psi, when you wind in more boost say 20psi, it doesnt make anymore power, like the turbo is out of puff at 17psi. my mechanic reckons splitfire coil packs will solve it all. the tuner said my coils were fine. dont want to spend another 500 for nothing, . cause i reckon its the turbo.

car mods include

fmi

pwr fc

profec b spec2 set to 17psi

555cc inj

fuel reg (malpassi)

r33 gtr fuel pump

oil cooler

all thoughts are welcome cause this is driving me nuts!

cheers people

rob

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Those specs don't spell a (what I call real) GT3076R . Compressor should be 76.2mm 56T with ~ 57mm inducer , comp cover should be port shrouded T04E 0.60 A/R .

Turbine should be 60mm 84T GT30 with an aprox 55mm exducer size .

Check out the turbos ID tag , unit number would be 700382-12 (cartridge or CHRA number 700177-7) if its the Garrett version of the HKS GT3037 56T .

Check to see if it has a genuine GT30 turbine housing as well .

A .

Edited by discopotato03

Not trying to start something here but i also had a problem with a turbo i bought through an online store. Turns out the turbo came from GCG also. The car was a 180sx sr20( my old wheels ) car had power fc, injectors, afm, exhaust, cooler, e boost, fuel pump and my car would not make over 191kw. i had the car tuned by 2 different tuners and both came up with the same conclusion. The turbo could not make any more power. Complression was perfect. The turbo did not look like the one in the pic, had different comp wheel. Turbo was the GT3071.

From what you have told me id be looking into the turbo side of things a little closer. Make sure you got what you have paid for!!

Good luck

I think people need to be clear before going around and rubbishing products/businesses or threads will be locked.

As for the car, and why its not making anymore power, 260rwkw is where you are at now. If you put 3-4psi more in and nothing happens then why not?

Is the tune right? Is there detonation making the tuner pull timing? Is the exhaust restrictive? Inlet pipes not sucking shut? etc etc. There are sooo many reasons and i honestly FAIL to see how it could be coil packs unless your having miss-fire issues... if the tuner is reccomending Splitfires without missfires - i'd question their level of skill substantially.

The front A/R wont be restricting it, so again, questionable tuner

I think people need to be clear before going around and rubbishing products/businesses or threads will be locked.

As for the car, and why its not making anymore power, 260rwkw is where you are at now. If you put 3-4psi more in and nothing happens then why not?

Is the tune right? Is there detonation making the tuner pull timing? Is the exhaust restrictive? Inlet pipes not sucking shut? etc etc. There are sooo many reasons and i honestly FAIL to see how it could be coil packs unless your having miss-fire issues... if the tuner is reccomending Splitfires without missfires - i'd question their level of skill substantially.

The front A/R wont be restricting it, so again, questionable tuner

my mechanic reckons coil packs, my tuner said it was out of puff at 17psi, just had no more to give.. wasnt knocking, air fuel perfect, i just think its the turbo.. if i have to ill take it off try and sell it, put another turbo on if still not making decent power then its my car`i guess...

thanks for your input people.

A proper GT3076 will do +300 with the correct Rb setup [RB30?], it will do 275rwkw 24/7/365, have a look at the R33 turbo results thread, heaps of them.

yep thats why im so not happy.plus its laggy. comes on full boost at 4700, i wouldnt mind so much if at least it was responsive... so crap power with big lag. i was loving my car more with stock turbo at 12psi. (215rwkw) at least it was responsive and had top end.. $4500 later and im just pissed off... i still reckon somethings up with the turbo

At that rate I'd be seriously checking for boost leaks - make sure all the hose clamps are done up, no ruptured anythings.... BOV is not leaking etc.

exhaust and cat have been checked, intercooler pipes checked, blowoff valve checked, all those things are fine... think its laggy cause of the angle they cut the blades or something, cause its a custome setup.

is this an external gate setup or internal gate with stock style turbine housing?

Something is choking the power and killing the response, it could be the turbine housing, it could be a cam out by a tooth or a heap of other things.

First you need to confirm the details of the turbo i think. If it's a big turbine in a smallish housing with cut back blades then you have a problem.

is this an external gate setup or internal gate with stock style turbine housing?

Something is choking the power and killing the response, it could be the turbine housing, it could be a cam out by a tooth or a heap of other things.

First you need to confirm the details of the turbo i think. If it's a big turbine in a smallish housing with cut back blades then you have a problem.

yes its a internal gate setup with stock style turbine housing, all the specs i wrote down on my first post....

i think it is a big turbine in small housing, cause when i sent it back to them for more power , when i got it back they said that they cut the blades so there on less of an angle, almost straight... i just can't beleive gcg wouldnt know all this?, im starting to think i know more about turbos, god help em if thats the case..lol

What you mean they cut the blades?

So its not the same turbo as you stated in your first post?

huh?, as i said in my first post they sent one out that wasnt making good power, so i sent it back and the one i have now is the one that they made to the specs i put in my first post, so part of what they said they did was cut the exhaust blades so there on less of an angle,. they reckon doing this would make it flow more, and or come on to boost earlyer..

So what was the specs BEFORE you sent it back to them etc?

I agree - getting stranger by the hour... always happens with threads like this

dont know. never got em. only got the specs for this turbo. the turbo that is on my car..

anyway, thanks for your feedback people.

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