lets say its a cracked head. I have a set of 305 heads sitting around. What would be the out come of 305 heads on a 400? The only upgrade is a 0.442 int./0.465 exh. cam.

Just foating some thoughts, but the question was is there a way to tell whats wrong before I take it apart? You know, like if you put oil in the cylinder you can determine bad rings or a valve.