have a customer engines .030over 454in a 68or 67 camaro and as dart 320 heads roller cam abit bigger 12to1 4000 stall runs a dom carb and it runs 10.50 with a bad stall and he did not like runing the hi rpm so i regeared it and it fell on it nose . i really did not think it would do that. i think his stall may not be rigth still. but he has a heavy car 3800 and big heads and carb with not much gear with a tall 29 tallslick