I have a big t3/t4 and it spools very well/fast. Especially considering I have a "semi" log-style manifold. You might be having problems elsewhere, not with the turbo. Boost leak?

 

The turbo is boosting up fine, it start to boost at around 3500 and i'm at full boost at around 4k, which is very good. I am just looking for something to spool up maybe 500rpms quicker. check this out

http://www.turbocalculator.com/sale-garrett.php

What do you guys think of the first one? How's the price on it?

 

gt28rs

will get you the power... and quicker than any other turbo...

you can also try the 71 if you want more power...

 

Your not going to reach 300WHP with the t3 super 60. Its to far out of its range
my numbers at 16 psi and 20 psi were no different.

250WHP is the max that turbo will suport.

 

Ye, the T3 Super 60 is probably going to be pushing it to get 300WHP out of it... it would be at the top of its efficiency range.

Plain old regular T3 will get you up there a lil faster... if you wanna spend three times more, you could get the GT28RS but thats up to you.

 

I'm working on getting a much better price on the GT28RS

I'll post up as soon as I know.

 

I dont think the GT28RS will support 300WHP, maybe the GT2871R but not the rs.

 

I'm just going by what other people have said, I've never seen a compressor map for it.

 

My car has a garrett gt28rs turbo and it spools from 3000rpm, 210hp, 16psi on the dyno tune.
The garrett turbo was rated at 350hp.

If I needed more power, acceleration and closer to 300hp, then I would need to upgrade these parts;
modified intake manifold (improves spooling)
modified throttle body (improves spooling)
rebuild and strengthen engine forged pistons, conrods, valves, valve springs, rings (boost to 25psi, 300hp)