The cam comes out with careful application of a BFH. You have to drive the cam retaining plug out through the back of the cam housing using the cam as a battering ram. There are some advocates who claim you can also drop it nose-first onto a slab of wood, but I don't think that's the best way.
The valves are super critical. The tip of each valve must be 0.850" +/- 0.020" above the upper deck of the head. The ONLY exception to this is if you run a re-ground cam and you want to correct the valve-train geometry. There are no cam bearings in the cam housing. The cast Iron cam rides diectly on the Aluminum housing with oil pressure.
Contact me at Primatech and I will put you in touch with our cam replacement instructions. They describe removing the old cam and breaking in the new one.
We believe we do a better job on OHC heads than virtually anyone. We've done more OHC heads in the last 3 years than most machinists will do in their career. For an example of a head we've done, see:
