I have a 1972 Cutlass Supreme with a 455 engine. When I researched the specs I realized that it developed 250 hp at 4200 rpm and 370 torque at 2800. A 1971 with the same bore, stroke, c/r, and carb develops 320 hp at 4400 rpm and 460 torque at 2800. Can anyone tell me why the difference in hp between the years? Will 200 rpm make this large of a difference? I haven't been able to find anyone to fill me in. :banghead:
do they come with the same cam?
possibly emission reasons. during the 70's the fuel crisis caused manafucaturers to change a lot of things to try to increase gas mileage and reduce emissions.
Definately the cam shaft, swap it out with the other year and just try to touch the dash under full throttle! :laughing:
I am not sure what year the jump was made. I was thinking it was the 72 to
73 year jump but could have been the 71 to 72 for Oldsmobile. The auto
manafacturers quit rating horsepower at the crank and started rating the
horsepower at the rear wheels with all accessories running. So it is
possible that your engine is putting out the same horsepower but it isn't