Ran into this while trying to find out how much a distributor that I have cost new.
Go to this link for info on Ford FE distributor gear wear and what causes it:
http://www.performancedistributors.com/technical.htm
Here's what it says:
Topic 2: Excessive Distributor Gear Wear on Ford
Excessive distributor gear wear can be a problem with Ford engines. Most of the time, the problem is a result from the use of a high volume
oil pump. High volume
oil pumps put a lot of stress on the distributor and cam gears. A high volume
oil pump is not necessary on a street driven engine that turns no more than 7000 rpms. Only extreme racing engines require the high volume pump. Should you use this type of oil pump, the following precautions will save your distributor gear from early destruction.
(1) Drill a .030" hole in the lifter/oil galley plug behind the distributor. This will allow additional lubrication on the distributor and cam gears. This will not lower oil pressure enough to hurt the engine.
(2) Ford oil pump mounting brackets have elongated holes. Due to this, the distributor shaft and oil pump shaft should be aligned so that the distributor turns freely before tightening the mounting bracket bolts. Failure to do this will cause a binding situation, thus damaging the gear.
(3) Stock Ford hex oil pump drive shafts are know to vary in length which could cause a bottoming or binding situation.
(4) Brass distributor gears can be used to avoid damaging the cam gear. Brass gears are softer and can wear out quicker than the cast gear, but will not cause damage to the cam gear. If using a brass gear, check it occasionally for wear.
Paul