Yeah, BEB, I agree with Chaplin, the arm HAS to move instantly when you move the throttle. If you have clearance at idle (that is, if it is "loose" and not in contact with the cam), then there's sumpin "rong", maybe a bent arm?
Easy way to check for clearance is to turn throttle to WOT and then use a screwdriver to push down on the pump lever...make sure it will still go down a wee bit while at WOT, and is not bottomed out.
My Holley book is at the house, check the Holley website and see if they can tell you which cam gives the biggest squirt. Check out this website
http://www.holley.com/HiOctn/TechSer...fo/TI-221.html