Portmaster

Well I'm going to go against the grain here and explain. The RPM Heads are pretty good but on a 331 they can get a bit stuffy near the top. Out of the box they flow somewhere in the 230 cfm range and thats below .550 lift. Being as you are using a Vac Secondary carb and dual palne intake I'll suggest a Comp XE274HR. It will give you a much wider torque band than any of the others mentioned and will be crisp. It will make a little rump at idle (very noticeable) and pull really hard past 6200 rpm where the heads will start running out of breath, the heavy hyd roller lifters will start reaching their limit. Shift this engine at about 5900 rpm and it will do well. Have the guy doing your heads to check the open pressure of the spring. You need from 290-320 lbs of open pressure for this cam. You also need .060 clearance between the coils at .565 lift. I'd spend an extra 80 dollars and get the matching springs for the cam. In this case the XE282HR is too big.

PJC Racing

The stock Edelbrock springs in those heads are pretty weak and susceptible to valve float at rpm. My valves floated with a FT 230 dur / .512 lift at 5500 rpm. I would replace the spring for whatever cam I selected. I may have missed it but what is your goal for the engine?

jerod187

hey ok i will look into the matching springs if i can afford i lol! and i will look intothe XE274HR, Also this car is gonna be more of a weekend street car jus kind of something to play around with after work and on weekends, might even drive it a daily for a little bit and take it out to the track on the weekends

mjr46

Gee I wonder why crane hasn't responded yet???lol..........can you say Belly up

jerod187

oo they wont outa business