[thstone]

Bent valves indicate that serious damage was done - especially if the engine was operated long enough for someone to say that "it was making a sound they didn't like".

You know that the tech ran it for awhile before he told the shop manager. Then they ran it for awhile trying to figure out what the problem was. Then the engine was probably run more as they verified that it was out of time.

I wouldn't accept anything less than a replacement engine. This isn't s stripped spark plug thread in a head that is a simple, fairly reliable, and well understood mechanical fix. You're looking at most of an engine rebuild. How are you going to explain an engine rebuild due to dealer caused damage when you try to re-sell the car? As soon as a buyer hears "re-built damaged engine", they will take $$$$'s off the asking price.