Vman73 said: Bill, no Holley expert here but hesitation is usually the accelerator pump or the secondaries opening too soon. Since you mention the acc pump seems to be working, I would suggest the secondaries. Does your Holley have vacuum or mechanical secondaries ?? If vacuum, it can be adjusted by changing the internal spring in the diaphragm. not sure about mechanical secondary adjustment, check out the Holley website, they've got some good technical resources there. There are also a coupe adjustments for the accelerator pump to consider, the pumps should have adjustment screws plus the nozzles can be changed to larger dia. holes to deliver more fuel, again check out the Holey website for more info. Hope this helps, let us know what you find.

The engine has good steady vacuum (27 inches) so it looks like the intake valves and idle adjustments are okay.

I looked at a Holley forum and got some good pointers there, but nothing seems to point to a resolution.

Thanks again!

73shark said: Too bad it's not a spreadbore Holley, then you could just swap it out for a Q-jet.  Problem solved.  

If you ease into to it a little before you mash it, does it still bog?

I've worked on a lot of Q-jets, but never a Holley.

danascar said: No idea on the cfm of the carb but just the fact that it is a double pumper I would think it's way too much carb for that engine.