Quote Originally Posted by 10SecS4 View Post
You can't compare a single turbo 1.8 4 cylinder to a twin turbo 4.2 V8.

Like Korben007 said, you're not going to be able to run anywhere close to 22psi to redline with RS6 turbo hot sides. You'll need larger turbochargers and even then you're going to run into space constraints, transmission limitations, etc.
Korben and 10Sec: I did not ask anything about turbos. Not sure why anyone is talking about it. Let those be my concern. As far as turbos are concerned, I know what I am doing. Believe me. And for those who do not know so much about turbos: The RS6 is a 2.1 liter, about 10% larger than a 1.8T. Specific HP is the same as the 1.8T in the Audi TT. On stock block, stock MAP, N75, we are making 680 HP on 2x4 cyl and 3.6 liter, with wastegate 50% closed (keep that in mind), turbo no even 'warmed up'. We expect that turbo to flow 800 cHP easy in twin configuration with 3 bar MAP.

So back to my RS6 specific questions, if you would.