I have just purchased a 72 nova it has roll bars, 12 bolt 3.73 gears, line lock etc. It also, has 28-9-15 slicks. I have a 74 nova with the same but the 72 has a super t-10 manuel and the 74 has a th350 with 3000 stall. The 72 will have a 501 hp 408 (flywheel) hp engine with 150 shot. I have never driven a 4 speed at the track only Automatics with stall coverters. I have head many different rpms. Just asking for some input.