Im going to be building a 327. Since chevy swears that they put a 327 4bolt main into a corvet way back when i decied i would take one apart to find out, it was a 2 bolt main. so here im stuk debeating weather or not to machine the bloclk for a 4 bolt or not. Will it make that big of a diffrence? but i really need some help on what i should bye for this motor. I want 350-450hp out of it i know it can be done but i dont know the specs. can anyone help?