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Anyone got any idea what a GT35R with a 0.68A/R would go like on a RB25?? im just worried with that rear housing it will come on boost REALLY hard at about 3000RPM and not make it all the way through the rev range.

Any experience in relation to this would be greatly appreciated!

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why buy a turbo with a 400+rwkw compressor and bolt a 300rwkw rear housing onto it? wrong way to go about it, smaller turbo with a bigger (relative) housing will give you a much better overall result.

a gt35 will not make enough boost by 3000rpm with any housing on it.

have a think about how much power your after with what sort of response and have a look around here, theres weeks of reading on here about turbo selection for rb25s

full boost at 4800 with a .68 arse doesnt sound right to me, sounds more like it may of had the 1.06 rear, ive been in a 33 gtst with a stock internaled rb25 with a .83 reared gt35r strapped on and it hit full boost at 4000 or even less if I remember right

Are you asking is there a better turbo to use or do you already have a GT35 with 0.63 rear and want to know if it will work well?

Better turbo would be a GT3076 with 0.82 housing. Yes the GT35 with 0.63 will still do good things.

Hey, I got a Rb30/25 with a GT3576 and even on the 30 it still takes till 4500rpm to hit 18psi. sooo a 3582 on a Rb25 is deffinitly going to be slower.

are you sure its not till 4500? my RB25/30 with 3582R (0.82 rear) is on 20psi a little after 3500rpm.

I don't know if you have seen the Video of Steve myburghs 180SX Sportsedan? It runs the small .68 housing on an RB25, The car runs down V8 Supercars with a novice driver and makes over 20psi by 3800rpm but it does struggle for traction when it hits and it has massive slicks.

That Video doesn't do that car justice, the noise of this thing bearing down the straight coming off Ford corner is insane. The screamer and induction noise is almost painful when standing near the track... stupidly quick car...

IMO if you were going to buy something new you should look into what HKS call the "GT3240R" - if you want something between a GT3076R and a GT3582R .

Its still in production and if like the GT3037S's you can buy the through Garrett without the HKS turbine housing your in .

Get a T3 flanged GT30 IW T housing and and get it re-profiled to suit the "GT32" turbine .

For those who don't know the "GT3240R" is similar to the GT3540R AKA GT3582R . HKS gets Garrett to crop the turbine back to GT32 84T dimensions and the compressor comes back a trim size from 56T to 54T . Compresor housing is the same but profiled inside to suit the fractionally smaller 54T wheels inducer/profile .

Personally I think anyone's mad not to run the Garrett port shrouded compressor housing on GT3582Rs if you use smaller A/R turbine housings .

The real answer in the power and response stakes is twin scroll turbo systems but until Garrett make twin scroll twin integral gate turbine housings you're stuck with the compromise .

A .

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