i guess a lot depends on you. the original cams weren't what i'd call hot. the original '62 413 and '63 426 "stage 1" were around 300 degrees .509 lift. the stage 2 426 was 308 .520 lift and i believe the '64 415hp used the same cam. the race stage 3 used and isky 1012b, fairly hot for street. for the original stage 1 and 2 i doubt the .050 duration was over 240 degrees. i ran a stage 2 cam back in the day and it wasn't radical. both the stage 1 and 2 cams had a wide lobe seperation, 115 i think. the 1012b was 108, if i remember correctly. an engle k65 will approximate a stage 1 415hp 426. it will yield around 295 degrees at the seat, 238@.050, .510 lift, like a little compression without needing a loose converter.