IMO, it won't be worth the trouble to BUY the heads, have them checked AND corrected if you are not going to port them. I cannot see 1500-2000 bucks worth of power without port work, because that's about what you will spend. Spend for a GOOD port job plus getting them corrected and I say go for it.
Damn. I thought I read that out of the box aftermarkets outflowed a fully worked over stock head. Maybe I would be better off just using the money to have my stock heads ported and all.
