Join Date: Jul 2004
Location: Redondo Beach CA
I'd hazard a guess to say there is not any defect in the accelerator pump system. The carb is most likely calibrated for an engine milder than the one you have, and as such the system will need fine tuning with a different accelerator pump cam and/or pump shooter. I'd try 2 degrees more timing, and see where that gets you. If there is a minimal improvement then I'd start by putting it back to 12 and get the acclerator pump assortment from Holley and go with one that offers more shot. Now that I think about it, you might even look at the pump cam you have now, most have a couple mounting holes, try it in a different one than is being used now. If you have a friend with some carb stuff you can also try a bigger shooter, don't know what they come with but even if you bought a new one they arent that pricey, probably has a 28 on it, maybe try or borrow a 31. I'm talking of course like you know what all the pieces are, if you don't please ask, no disrespect intended if you already know.
69 Mach One, 428CJ, Legend 5 Speed, 3.91's.
Last edited by gregb; 06-24-2011 at 02:06 PM.