It's not this hard to understand.
Start with a well built short block assembly. Roughly anybody's stage 2 or stage 3 shortblock will do. Burschur has some good pricing on theirs. If you want to build your own just follow their recipe. I'm partial to the 2.4L for a DD or street car, but that's just me.
Add a well built and ported 1g cylinder head. Add a good set of higher level cams (HKS 272/272 or 280/280, FP2's or FP3's).
Bolt on a good intake & exhaust manifold.
Build a fuel system that will flow what a pair of Walbro 255hp's will do or better. 1000cc injectors.
3 to 4 inch exhaust all the way out.
Biggest and best intercooler and pipes you can fit in there (air-to-air or water-to-air) or run methanol injection.
A turbo that will flow 75 lb/min of air flow (FP3575, T67, etc.) with a good exhaust side and be prepared to go over 30spi. You could go smaller on the turbo, but you have to supplement it with nitrous to make up the power difference. 600whp will require 700+ at the crank.
AEM EMS or DSMLink in the hands of somebody who knows how to tune (if that's you, more power to ya).
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