I'd just like to comment about the s2k not being able to make much more power.
Its not even turbo charged and the factory pistons are forged. Not much more power? Ive seen 9psi of boost (properly cooled) supply the roadster with enough air to put 345hp on the ground. And its not like 9psi of boost is any kind of strain on the turbo...
Can you imagine that motors output at 20+ psi? With the right internals, that would be incredible thrust.
The way I figure it, (the boost raising the VE over 200%) it would be anywhere from 560-600hp
That would be nice to see.