Rb30 What Turbo's To Use?

[cul8tr]

I have a circuit racing Commodore (sport sedan) that i am doing an engine conversion on. Starting with an RB30 (before you ask i can't use the RB26 head) so the stock head with remain. As throttle response is most critical i am considering making a manifold and putting 2 turbo's on it. At the start i am looking for 500hp at the flywheel then 600 and finally 650. Does anyone have a suggestion on turbo's to use and why ? thanks

[Cubes]

www.calaisturbo.com.au

[sproosy]

werd