All the rich guys tell you buy aluminum> Where will they be when they crack strip or better yet warp> The question is if your going to race it go ahead with aluminum. If not try JB weld after a drill on the ends of the crack. Frankly if it were me I would probably braze it or just JB weld it but I'm old and don't know nothing I have seen too much BS with cheaper aftermarket aluminum heads yes they work but leaks leaks and more leaks especially on a non decked block Said before too many non racers using race only parts and seeing the piss poor results