There is only one good way and that is to remove the gear, machine, file or sand down the spacer ring so that the spacer is just .001" thicker than the retainer plate and reinstall it.
You can try using a press to push the gear down further but I've never seen that work. Ideally if you use the metal cam gear you can put it in the oven at about 350 degrees and the cam in the freezer for about 3 hours and then install the gear.
Some people will tell you that if you just press the aluminum gear on to the camshaft at the same temperature it won't work as well, but I've never received any instructions with any of the gears I've bought and I know back many years ago when we actually had machine shops in Dallas the folks just pressed them on at the same temperature.
If you use the fiber gear, I would not heat it up...I think it used a steel center and not aluminum so it may be different. I have also seen people machine the front part of the cam completely level with the gear, drill a hole, thread it and use a screw and a large fender washer to keep the gear from moving outward and I've seen people drill two holes in the slot between the cam and the gear, thread those and use set screws to keep things from moving.
A few weeks ago Jerry mentioned he was planning on reaming the inside of the gear (to make it a tight but moveable fit) and using a retaining screw so he could move the gear advanced/retarded to adjust his valve timing. I don't know if he did that yet, though. I don't know if wear causes these to develop a greater tolerance or if they just never were installed right or if heating/cooling causes them to move. But I do like the idea of using some sort of mechanical means to keep them in place.
Some engines use spring loaded rotating buttons to force the camshaft back toward the rear of the block and I suppose somebody could do the same with the stovebolt engine. All the manuals I have say .001" to .005" max.
Below is a camshaft I bought around 1997. All I know is that it is a hydraulic lifter Sealed Power cam. I also got a new set of Sealed Power lifters with it, but I'v never used it. As you can see, the gap is .005" which is right at the outside edge.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
