formulaok

I have just recently purchased a 93 271 sr1 that i am redoing. The original setup was a single 502 mag efi. the x dimension is very conservative with the propshaft centerline between 7 1/2" to 8" below keel.

I am reglassing the transom and and installing a 700hp supercharged bbc. I need to raise the x dim. but do not know how far to go with it. Formula says i should be able to raise it without any negative CG changes. Bob Teague said I could raise it, but he would rather me change the lower to a shorty and keep the engine low, but he had never worked on this boat before. That is not in my budget

does anyone have any experience in this hull and how high to raise the x dim? also, what 4 blade prop is the best for the added x dim? What speeds should i be able to hold with that power(what kind of prop slip could i achieve.) Any help would be greatly appreciated