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I built a 360 ci flat top trw , flat tappet cam 258-266 .570 lift, steel darts 2.02-1.60 valves 1.82 PG tbrake 29 tire 84-85 camaro has run 7.18, 8" conv mabe 5.14 gear. very trouble free but this cam is 30 years old. I would build a roller today with the problems we are having with flat tappet cams. Later J.Smith 4621 racing The SledgeHammer. bjuice the zipper has seen this car run.