Upshur Twin valve timing

[Gordon]

The cam lobes are made up of four arcs with known radii and center locations. If you machine the parts to the print, you will get very close to the design valve timing. You can locate the arcs using a cross slide rotary table, CNC, Volstro head on a Bridgeport, offset on a lathe faceplate (for the flanks), or eyeball to a template drawn using a pencil and compass, scanned, and scaled down using your printer. I admit I have not tried to measure the valve timings, but am confident they are close to the design values because I know that my geometry is close thanks to CNC. The geometry is rather deterministic, shall we say.

I am embarrassed to say that I never thought to put the camshaft in the rotary table to position the second cam. That should have been obvious but sometimes I just miss the obvious and go directly to the wrong method. I used your method of using a template and eyeballing it.

I am curious as to how you came up with 108.75* for the angle between lobes. The drawings show 101 to 102 and 108.75 seems rather deliberate.