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Currently my R33 GTST is at the tuners again. They having trouble getting decent power out of the car. Curious to hear peoples thoughts.

Current modifications are;

Rebuilt motor & reco head 10,000kms ago

GTX3076R bolt on turbo, FMIC, intake.

Wolf 3D v4.

Full exhaust

044 fuel pump & nismo 740cc injectors

At 9 psi of boost it makes 190rwkw

At 16psi of boost its currently making 220rwkw and starts to detonate so they must modify the timing they said.

I thought it would be alot higher than this for that boost level?

Thanks.

Edited by GotsWapan
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what does full exhaust mean? those symptoms are bit like the exhaust is blocked, like a cat or a restrictor..

I think the 9psi to get 190kw is probably right, with 15psi i was getting 260kw so you should be around that..

what housing is it?

Now you mentioned that it reminded me of this -

http://www.skylinesaustralia.com/forums/topic/403526-rb25-gt3076r-turbine-housing-size/

Sounds like a similar thing.

Certainly sounds like just another case of butchered housings. If a GT series have issues with them, it's only going to be worse with a GTX given they are meant to make more power.

If it's not the housing

- Exhaust

- Timing belt is out a tooth possibly

Currently my R33 GTST is at the tuners again. They having trouble getting decent power out of the car. Curious to hear peoples thoughts.

Current modifications are;

Rebuilt motor & reco head 10,000kms ago

GTX3076R bolt on turbo, FMIC, intake.

Wolf 3D v4.

Full exhaust

044 fuel pump & nismo 740cc injectors

At 9 psi of boost it makes 190rwkw

At 16psi of boost its currently making 220rwkw and starts to detonate so they must modify the timing they said.

I thought it would be alot higher than this for that boost level?

Thanks.

Hey mate, have you got the detonation verified with headphones or is your tuner just running of the knock sensor?

Reason being, I used to get alot of noise which the knock sensor interpreted as detonation.

I'm also running a GTX3076r on my RB25 and make jsut a tad over 300rwkw on 21psi, so would expect yours to be around the 260rwkw mark like SIlverS2 said :)

Well if you runit on stock manifold as a bolt on turbo internally gated on that housing its not going to make lots of power. GTX3076 is ideal for external gate. Also I didn't see metail induction pipe in your mod list, you will need a 4inch metal induction pipe for that turbo.

Not sure of that turbodragon, I assume its with headhpones. Its a fairly reputable workshop and they do alot of RB25 work and work on VLs. I havent spoken with them today. Will ring them soon

Best to ask them and find out. Could save you a lotta time and cash if it was just phantom noises coming from the harmonic balancer or soemthing lol

Plenty run a 3" that just steps out to 4" @ the comp housing to get a hose around. In fact that's how most are done come to think of it given a Z32 isn't 4"

Yep, Z32s are only 3" so 3" intake pipe and a 3"-4" reducer at the comp housing inlet.

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