About a 1000 horse is all your going to get on a conventional hemi head. And that won't happen with pump gas and a tiny cam. The numbers will increase slightly with a millenium style head, but without compression and cam, the increase will not be drastic. If you want a hemi to run on pump gas with hydraulic cam it won't see 4 digit power numbers even with 600 inch. Big motors don't always make big power, you reach a point of diminishing returns.

No way you're gonna make that HP number on a NA street engine. EFI and turbo, sure, absolutely, 1500HP is do-able on E-85. Supercharger, yeah, that's doable too.

In a light enough car, a 6spd can live, there's 1500hp vipers running mid 8's on a 6 spd.

My chassis shop has two 1200HP turbo stroker small block Ford's living with 6 spds and McCleod clutches. Yeah, they're light cars. S/F.....Ken M

As stated before contact Tim at FHO
HE WILL answer all you questions.