[Mike Taylor 3601]

if you want to get a little deeper you can gain a lot of cam,of course it has to match specs for duration, overlap, and lift. cc heads you'll probaly find they need .030-.060 milled to get down to min. cc. match valve springs to press specs you'll probaly have to get specs from IHRA to come up with duration,overlap, and spring pressure.
With a pure stocker cam probaly need 4000-4500 or so on converter but w/lock up could cruise like stock converter.
4.56 is lowest you can get for 7.5 but w/ od I think is .77 which would make 3.51 final,take 4.56 and mutiply by .?? (od ratio) will give you actual ratio in OD.
Don't spend much on 7.5 when can go ahead and go 12 bolt.I spit 7.5's w/ auto out of my pure stocker when first built it
Mike Taylor 3601