Do know what cam you have? Is it hydraulic, solid, roller, what? What are the specs? Any cam over .490" lift with early stock heads is going to likely cause problems with coil bind, hence broken rocker arms, bent pushrods, etc.. But if you had a broken valvetrain component you'd have a dead skip on one or more cylinders. If you have a solid cam it'll be a little noisy from the lash chatter, but you haven't given us a lot to go on. Cams don't cause errrant noises and misses--mismatched parts do. I don't know what to tell you without knowing what is in your engine.