I have a 74 olds 455 with J heads in my 71 442 convrt I have the build sheet from when the motor was build it claims is 40 over 10:1 comp 71 w30 cam. I have a edelbrock performer intake edelbrock 750 carb hei ignition & headers. its is my first olds but it does not seam to like to rev at 4800 ot is out of breath. I took it to the track & ran a 13.9 at 101 with a 323 rear But I feel I should get a lot more out of it. Is my problem heads or cam or both. what should it rev to & any cam imput would be great thanks.

The stock HEI when it gets a little older its only good for the mid 4,000 RPM range. You should try a upgrade on the coil, module, and wires.

__________________
Luv the smell of NITRO in the morning.

The hei & the whole motor are new about 2k on it.
should have said that before.