12 Second N/A Slant 6?

Bill Dedman 1.6 didn't make much difference but i find rocker ratio in my program usually don't make much difference so i wouldn't use that as a deciding factor especially after what PowerWagon896 said.

Just for fun i did a 170 /6, 800 cfm, 12.5CR, RustyRatRods head, Headers, and comp cams 20-231-4 specs 1.6 rockers.
306hp@7500 245ft-lb@5500