If you're gonna replace your heads, get in touch with a reputable machinist for advice. With Aluminum heads, you'll be able to increase your compression ratio(increasing HP) and still run pump gas(several other details to consider). With the right info, your machinist can reccommend the best configuration to get the most bang for your hard earned, kicking a$$ in Afghanistan, buck.
I'm a hobbyist. Not a professional. Don't be hatin'!
