You can make 250hp on a bone stock engine with proper fuel upgrades. A built 3400 on 10-12psi with a decent sized turbo would put you in the 300-325whp range I'm guessing. Then you'll want to look into forged pistons and rods, and basically everything [ion] C2 mentioned. Blackjack would be the guy to talk to about the specifics on a turbo 3400.
__________________
|