[Barry_R]

Originally Posted by legenmetals

I scrapped my aluminum tensioner after looking at the quality of the machine work on it. I found original ductile units for my two aftermarket cammers. I would like to point out that the aluminum heads have a standard 7/16 ( I think) bolt and jam nut that adjusts the tension on the idler arm and chain. The original adjusting bolt has an interference fit for the cast iron head. The interference bolt will eat the threads in the aluminum head. The standard s.a.e. bolt fits loose in the aluminum head so make sure that the jam nut is locked down tight or you may jump timing.

Ran into that issue too. Ford had some kind of fascination with interference threads back then. Interference threads are an evil and wicked creation which should be banned from the planet and erased from the memory of mankind.