I think a fully ported set of -1s, a custom roller, bigger headers, and the -3 intake will get you there. Talk to Dwayne Porter. I was in the process of building a 4.25" stroke version of the same type of setup you have before I bit the bullet and built my KB block hemi. My car is similar weight and I also wanted 9s NA on pump gas.
My plan back then was a 511" RB w/ the big CNC ported Indy -1s.
I have been running 110 so race gas is no issue. This car see's basically no street miles and if I can get the compression up I will run c16 if I have to. I just assumed since these other heads all flowed so much better then mine to start with it wouldnt be that much work. I did already buy a new cam but not possitive I am going to run it. It is a 278@.50 with .660 lift. I figured I would end up with the new rockers being 1.6 ratio.
