Motorcycle Repair: shovelhead valve/piston collision, valve piston, faint marks

Question
Purchased a "best of everything" Shovel motor on Ebay. 93" S&S forged pistons,dual plugged ported heads, Andrews 3 grind cam w/ solids, and a SERIOUS ticking in the top end.
Pulled it apart and found faint marks on both exhaust valves,matching marks on pistons. How can this happen w/solids, and would a B grind solve the problem? Listed lift@TDC for the 3 grind is much lower than the B, Am I missing something here?
                 Thanks,
                         Mike Davis

Answer
Without knowing what was done to the motor there are several posibilties. First, the pushrods might have been to tight or not adjusted correctly. The pistons might not have been put in the right direction or the wring pistons were put in. Changing the cam will not solve the problem. The cam should work if the motor was set up right!
Good luck and happy riding
Mike