Chip I have been working on chev sixes for 40 years now and I have noticed a lot of stock distributors wobble and not thought much about it. I think you will find cam gears do not run as true as one would like. Now with the HEI setup with the distributor clamped solid, I can easily see how a bind can occur which could pull the distributor down with force into the top of the oil pump. I suggest using a stock distributor (maby with Pertronix if you want) for the summer and see how everthing else works and pull it apart this winter if you want to change the cam and try HEI again. Dave
