Ummm,
Not to sound like an ig-nor-ay-moose, but what are pushrod springs? Same thing as "valve springs"?
I'm only familiar with the 216 engine, but I've not heard of any springs in the camshaft-to-valve circuit other than the valve springs, by which I mean the spring that surrounds the protruding stem of the valve which forces the valve in a closed position - until the camshaft eccentric pushes up on the tappet, which pushes the push-rod up, which pushes one side of the rocker arm, which "teeters" to push against the valve stem and spring, opening the valve.
With the valve closed, the clearance should be enough to hold the pushrod in place between the rocker and tappet, but not so much that it won't rotate or "spin" when the valve is closed.
This, of course, all pre-supposes an overhead valve engine. No rocker arms in a flat-head engine (I think?). Still valve springs, though . . .
Not sure if this helps. As usual, I'm rambling . . .
-Michael
