I had a friend who had one with prepped stock rods, balanced, hv oil pump with pick up mods, ported heads and mechanical cam that he red-lined at 7800 and would ocasionly see 8000, never had any problems except holding valve adjustment. Others are right on, it will rev like a small block and turn RPM's with stock componants the brand X could only dream about. Most stock 383 magnums would turn 6000 + easily. I colapased a lifter and bent a pushrod once in my 70 roadrunner with stock 383 when a missed shift reached 6300, lol.