Originally Posted by TheEngineer

There's no replacement for displacement, so a SBC with 400+ CIs is the way to go! Additionally, I believe a broad power-band in a car like your's (but typically with a Power-Glide) is also very important. So, a 4" stroke crank will help with that.

FYI, my SBC 427 stroker with 4" crank will easly turn 7500, but I typically shift it at 7200 bracket racing.