What about any speedway cars? Surely some of them have to have some big hp na v6 engines? Anyone know about any of those?
yeah, you can make decent power but it's always been a lot easier to use forced induction.
The V6 bottom end is fairly much bullet proof, the problem is in the heads, they don't have the biggest ports to work with.
I believe you can get a set of flat top pistons from precision to suit, that will get the compression right up, port the heads, get a cam to suit, run some E85 to suit the high comp and you'll get close to matching him for power.
If your serious, jump over onto the AV8 forum and talk to TK383 he's built a tough little V6 combo although these days he's not taking on much engine building work as he's concentrating on head porting.