my car ran minted with bent valves,tuners didnt even know what was up with it unytil they took head off,so thats not always the case[/quote]

Sorry m8 BUT if your car ran mint (your words) WHY would they of had to take the head of then NOT to find out some sort of running problem it MUST of HAD then OR do they just like taking heads off mint running engines

I think you would be better of taken engine out and rebuild the whole thing as just changing the ends will NOT be any good IF it was knocking m8 as Dave has said ends,crank reground,maybe rods(due to them having shells spin)oil pump and the list can go on m8