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Hi there

I'm new to the forum. I've read lots of turbo related threads on here, but couldn't find a definitive answer to my question.

I want to build an extremly responsive RB26.

I wanted to use the -9's, because of the good feedback in this thread: http://www.sau.com.au/forums/topic/322850-garrett-gt2860-9s/

Now a company here in Germany told me to use GTX2860R because they should make boost earlier than -9's they said.

After reading the GTX thread in here, lots of people aren't that happy with them, especially with the response after on/off throttle.

It's a street car for slow roads, I want an early spooling turbo an great response when on/off throttle or after gear changing. I don't care about max power. Around 500-550hp at the flywheel is enough for the streets I'm driving. And I don't want to rev the car above 7000rpm everytime.

I will get Poncams and adjustable cam gears as well to adjust it for even more response.

Has anyone driven both turbos an know which one to get? Can a GTX2860R really respond better than a -9?

Thanks in advance and excuse my bad english please.

Edited by GT-R David
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https://www.sau.com.au/forums/topic/449379-gt2859r-9-vs-gtx2860r-response/
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Almost like stock just with more power :-)

If you want response like that, rebuild the standards with steel wheels.

-9's are a bigger turbo and they feel like it too. -7's are a bit more responsive once again. They both fall off a bit power gain wise past 20psi.

Listen to piggaz about the cams. Many people make the mistake of using too high duration which ruins response. Adjustable gears are a good idea though.

If you only want 500-550 at the flywheel then forget the GTX and grab some -7 or -9s. 7s respond better and are generally cheaper than 9s but they don't have as much to offer in the top end.

Good luck

I've heard that the GTX's will spool slightly (300rpm maybe?) faster than -5's. In the end though from powercurves i've seen that's still not the sort of thing you'd want for a dedicated street car, i'd say go -9's, i'm pretty sure that's the route i'm going to go down in the future aswell.

But that's just what i've heard....

-9s here with full boost at 3800rpm 20-21psi

Built motor blah blah and 272 10.8mm cams

So can be done will be looking for even more response on the new motor with higher comp and e85 so early next year will have results

What's your current power? I'd always figured that the limit on these turbos is ~320awkw's but people seem to be getting 350?

Something like a high comp 2.8 stroker that's dedicated to E85 might make a perfect combo really, if you can have full boost by ~ 3500rpm but get upto those sort of power figures

What's your current power? I'd always figured that the limit on these turbos is ~320awkw's but people seem to be getting 350?

Something like a high comp 2.8 stroker that's dedicated to E85 might make a perfect combo really, if you can have full boost by ~ 3500rpm but get upto those sort of power figures

I've personally seen -7s do 365rwkw in a 34 GTR on E85. 320rwkw is about right on 98 though. -9s a little bit more.

What's your current power? I'd always figured that the limit on these turbos is ~320awkw's but people seem to be getting 350?

Something like a high comp 2.8 stroker that's dedicated to E85 might make a perfect combo really, if you can have full boost by ~ 3500rpm but get upto those sort of power figures

Makes 350kw on 98

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