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Gt30 .63 Or Gt35 .63?

hairdryer33

By hairdryer33,
in Engines & Forced Induction

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Blackkers Experienced

Blackkers

Posted
Posted (edited)

38mm will be fine so long as you plan to run a decent amount of boost.

low boost + big turbo needs a bigger gate

GT35 size turbos don't really belong on a RB25 street car. a .63 rear on a GT35 turbo is a mismatch. Too much compressor, too little turbine.

GT30 with a 0.63 rear housing would be nice on the street but 0.82 will give you better top end and a few more usable top end revs.

You could always go GT30 with .63 rear and E85 + 22-24psi externally gated for around 330+ rwkw peak. usable boost would come on just before 4000 probably. That would be a mean street car

Edited by Blackkers
scotty nm35 Grand Master

scotty nm35

Posted
Posted

I agree, you can get away with a 38mm if the flow into it is optimised. Just welding it on a 90 won't cut it.

There is perhaps 200 rpm between the housings, there are also other housing options if you are going external gate. The Taiwanese stainless Tial knock offs are pretty good from my testing, and Kinugawa make some good ones in various sizes.

GTScotT Grand Master

GTScotT

Posted
Posted

The kando 10cm is 1/3 of the price and gives you an inbetween size (.7x)

I've used the kando 12cm (.89) on a GT30 core and so far have found zero drawbacks. I have also seen a few in action and results indicated they did exactly what the specs implied.

Far better value in total if you buy a garrett CHRA and kando housing separately.

Ben C34 Grand Master

Ben C34

Posted
Posted (edited)

I've got a brand new kando gt30 12cm for sale at the moment with Vband. You should use thar ;) 150 delivered.

Also have 3076 but with internal gate .82. Don't want to seperate it.

Edited by Ben C34

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