Interesting specs. That closing point would be "normal" on a much larger cam. So it will bleed a ton off at idle and low speed. You can try to lower that roof as much as you want. No way it will efver have any quench value. But that cam will tolerate a bit more static ratio without problems. I aim for dynamic of 8-8.1 max on iron heads and torque peaks below 3500. I'll go as high as 8.5:1 with alumimnum, decent quench, and higher peaks. You could mill the heads, but you'll need to mill the intake flanges too, adn probably either buy shorter pushrods, or rocker shaft shims to get the geometry right. You're spending either way.
In keeping with my budget , Im using a cam I had bought 8 years ago, and making it work. I already have a car w/ smaller cam , and want to push the limits. I haven't purchased pushrods , or head gaskets yet, so thats not a problem.I would like to get the Cometic mls gaskets , .040". Thays why I'd like to whack the heads about .050". I've shaved stock heads .060" before w/careful attention to valvetrain geometry, and that 360 still run strng. It's a'79 smogger w/dished pistons & .025" gaskets to get close to 9.2:1 , and runs on 89 octane.
edit: IMO, you're overcammed. you could use a thin gasket (.020) and get 10:1. But a better cam choice with the less static will feel and be faster in a street/strip car A lot of port work was done to the X heads, so I beleive they can support more cam.
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