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No doubt this question has been asked on here a few times and I apologise for asking again but i could do with everyones opinion on this.

I have a 34 GTR with a few mods to it and plan to do more.

It has CP forged pistons, ACL race bearings,Manley i-beam forged rods,n1 oil and water pump,tomei head gasket,twin 3inch,greddy t517zr turbos,HKS dump pipes,nismo cooler,nismo oil cooler,nismo 660cc injectors,nismo fuel regulator,greddy radiator,apexi filters,apexi ECU,nismo coppermix twin plate clutch.

On 15PSI its making just over 300KW.

I want to get around the 400-450kw mark. Its strictly a street car and I want it to be responsive from the get go.The greddy turbos on there dont really spool up til around 4000rpm..it has alot of top end power but down low its abit laggy.

I plan on doing more work too it...tomei cams,greddy cam gears,haltech ecu,bigger injectors,e85,greddy manifold and intercooler piping,tomei manifolds,tomei oil pump and baffle kit and bigger turbos,more boost etc

Here lies the dilemma of what low mount turbos to go with??

Reason im staying with low mounts is the rules here in SA are bullshit and they will pick on anything they can hence why i dont want to go a single either.

Ive heard good things about garrett turbos but just want all your opinions as to which would work the best with the combo above and what i want it to do.

Garrett -5,-7 or -9s??

Thanks

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https://www.sau.com.au/forums/topic/445375-best-turbo-choice/
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-7 and -9's won't do the figure you want. What you have at the moment with some boost up its bum will prob crack the 400 mark on E85, other than that it's -5. There are a couple other options out there now. Check out this discussion. http://www.skylinesaustralia.com/forums/topic/445007-the-frankinstien-twin-turbo-thread/

You do NOT need Tomei manifolds. They do a really good job as a door stop or a paper weight and thats about it. I would also suggest ditching those split dump pipes and replacing with bellmouth/open style pipes.

Do you plan on stretching the capacity abit? IE Stroking it? At the end of the day, you're lugging around 1600 KG plus of car with a smallish capacity, short stroke, relatively lowish comp turbo charged engine. It's going to need a few revs whatever the turbo choice.

There is plently of info in the forced induction thread about this. Have a decent search.

As already mentioned, the RB26 dyno results thread is a good place to start.

Failing that maybe have a read through this thread - it's long and some of the earlier posts might be outdated so start from the end and read back.

http://www.skylinesaustralia.com/forums/topic/251820-got-over-400kw-atw/page-153

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