As I said in the one of the other threads on this same subject, any optimally designed cam will have the nose of the cam at the same height (radius from cam shaft centerline) regardless of lobe lift. The difference between a high lift cam and a low lift cam will be in the radius of the base circle, not the radius of the nose. The nose radius should be just less than the radius of the cam bearing journals (just allowing the cam to be installed down the tunnel). Sure, you can design a cam with a smaller base circle and smaller nose radius, but in doing so you are either increasing side loading on the lifter or reducing the ramp rate, or both. I want neither of these in a cam that I use.
As JLMounce points out, with higher lifts we should be concerned with the oil band coming out the bottom, not the top. And 68hotbird, I appreciate all of the great information that you have been providing, but if you show me a cam with a nose that is significantly lower that the journal, I will call it a substandard cam.
Just for fun, I happened to have a Melling SPC-7 (068) on my bench. I measured the nose radius and found it to be 0.020" less than the journal radius. I am guessing that is typical with production tolerances.
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