Originally Posted by hunnerdean
I'm rebuilding an 86 351 windsor and I'm looking to upgrade the cam and heads. I'm almost set on Comp cams magnum 280h with 9:1 compression. Does anyone have any suggestions on a good set of aluminum heads for this cam? Any help with what I should also replace as far as lifters, pushrods, and rocker arms would also be helpful.
Alloy heads conduct heat very efficiently, litteraly sucking energy(heat=energy) out of the combustion chamber. To offset this you have to up the C/R 1 point. 9:1 in alloy gives same result as 8:1 with iron heads. You'd have to go 10:1 to get expected results of 9:1 in an iron head.
You'll need new lifters with the new cam. Check with the head's manufacturer as to rocker arms & push rods. A lot of aftermarket heads have things that wont accept OEM parts, you need to know what will & won't bolt on before buying. Stuff like intakes, ex mans/headers, rocker arms, valves, ect.