Motor rebuild

The engine was probably linebored. Thats when the caps to the crank go on the engine block and they bore out the crank journal to make it right. This shortens the distance to the cam. You end up with a loose chain even when it's new.

The fix would be a MoPar timing chain tensioner. There cheap and it takes up the slack. OE on Magnum engines. You can get one @ Mancini racing.

http://www.manciniracing.com/