If by stating E heads, you mean Eddy's, then you don't have a head problem you have a compression issue. If your at sea level about 10 to 1 or 10.5 to one is all your going to be able to get away with on pump gas and aluminum heads, 9 to one on iron heads. If you go to indys, your going to get the same results unless you go way up on your chamber size. You need to pull the pistons our and take some metal off if you want to run pump gas on the street. If you don't, and want to run race gas, then let the good times roll. We are at 4500 feet, and I have done a lot of playing around with compression and aluminum heads, the most we can get away with is 11.5 to one with a big cam. That is real border line, 11 to one is the best bet. But our air is very seldom below 6000ft in the summer.
Earl
