Simply put Ford has both tensioners facing down.   This works as it should on the driver's side.  But it puts tension on the driven side on the passenger side.  This allows for a variation in intake cam phasing from one side to the other. This piece simply swaps the piston 180* to tension the slack side. It will be just the block and you will have to swap your parts onto it. Here is a link to a write up of how it can be done - Click Here HOME Install Instructions Future Development Useful Links Price List $195 Free shipping in the U.S. Combine and save with a set of new 8mm pins made by ARP. $260