Hughes will grind any of their cams on a wider lobe center.

My old 440 had Eddie Rpm's, and a 304/640 Ultradyne flat tappet. Ten teens on motor typically in a 2850 lb car, with a glide, and 4.56s. 9.60's on a 225 hit. 8.96-146 with a second 200 stacked on top, had to go to 4.30 gears to get to 149 mph. It was not a particularly efficient cam on Nitrous!

My brother's Gremlin has a 440 with Indy SR heads and a howards flat tappet 272@ .50, 639 lift on a 108, and he's been 8.95 at 3000 lbs, but spraying a ton. 4.56's and a glide, and the gear really hurts him.

My first recommendation would be, a tight aggressive 9" or bigger convertor, and 4.30 or 4.10 gear, that will be more important than the nuances of a flat tappet cam.