Posted by Gypsy Jim (IP: 24.4.252.68) on December 19, 1999 at 22:37:29:
In Reply to: Re: Harmonic balancers posted by Charlie on December 19, 1999 at 13:34:59:
Prior to 1970 Ford used three bolt holes to hold the drive pulleys. The the pre 70's pulleys used were smaller, too. They also changed the timing marks in 1970 from the left side of the motor to the right. Another big difference, as I found out this summer when putting an ATI damper on, Ford installed the keyways in three different locations during the 70's. An easy way around this problem is to get a timing tape from Summit and put it on your harmonic damper. After you check that it is lined up properly, spray over it with clear lacquer (it's easy to do from the bottom of the car).
By the way, a good damper makes tremendous diffence in the smoothness of the engine over 6k RPMs.