Your probably right 4onthefloor, I went with a Howards cam and new guides but old intake valves you can see the results here in V8 Reason
http://community.webshots.com/user/zeker6
what a sorry day that was. I think the unworn portion of the valves tightened in the new guides (Head done by a machine shop) because of the higher lift got a tap from the piston the rest is history, The darn intakes were the only thing not new in the valve train . Zeke

The Amish Connection
51 Chevy 1/2 ton 5 window,Vortec hotrod, no horse