Join Date: Aug 1998
Location: Waldorf Md. USA
Cam walk will not normally cause distributor gear wear. One thing that will is too much oil pressure, like some of the high volume pumps have. Most people do not realize that 99% of the "drag" on the distibutor gear is from driving the oil pump. The distributor itself turns very easily and really does not put any drag on the gear.
As far as the bronze gear goes, it strictly depends on the camshaft you are using. Steel billet cams require a Bronze gear, like John said, However, there are roller cams that do not use a bronze gear, so you really need to check your cam card, or call the manufacturer to determine the correct gear for YOUR camshaft. 1/8" play is quite a bit for the distributor shaft. You might want to take the cap off and inspect it for signs of damage. It almost sounds like the distributor is going down too far and forcing the shaft up. Try putting the distributor in without the paper "washer" under it. It should go all the way down against the intake manifold. If it does not, it is bottoming out on the oil pump drive for some reason. These are some of the things you need to look at.
Hope this helps,
Advanced Automotive Machine