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[QUOTE=Pete;52570]"could be beneficial in not exposing the edge of the lifter to the camshaft lobe lifting ramp in the most radical racing cam designs. "
That doesn't happen in any cam I have ever seen...It may appear to but actually does not touch the edge...If it did the cam and lifter would be toast in a short time.
The reason for using a larger diameter cam blank in a flathhead is because at anything over .420 lift on a stock core you can't get the cam in the block..To get "more cam" you need to increase the lift along with the RATE OF LIFT...On the Isky 505A and several other manufacturer's cams with more lift they either run the cam in the block or bore the cam line and put inserts in.
QUOTE]
Pete this paragraph illustrates exactly what I meant. In my original statement I was merely pointing out something I would change (cam diameter) if one could do a "clean sheet" redesign of a Flathead Ford. With nothing to help multiply valve lift the cam bears the whole burden. In a perfect world I think a larger dia cam would be nice. As far as the lifters I guess I retract my statement to a point. While the stock Flathead Ford lifters are certainly adequate they too could be enlarged so as to focus the cam lobe footprint more within the diameter of the lifter. If a tomato can could represent the lifter and your finger the cam lobe's point of contact we can easily visualize this. When the finger tip is in the very center it is easy to balance the can, just like when the lifter is riding on the heel of the lobe touching it in the center. Slide the finger tip past center and the can wants to tip more and more just like the lifter wants to as it rises against the camshaft lift lobe. The process is repeated in reverse down the back of the lobe. You start building taller camshaft lobes and that moves the range of contact much farther out near the lifter margin. That's taxing on the lifter. That's all that I'm talking about.