I have a mild 455 with a Holley 750 on it. Brand new motor seems to idle fine my problem is when I give it full throttle it either dies or hesitates then picks up. When driving it is fine after you get going. So after research I am thinking the accelerator pump nozzle is too small. It is a .031. So with no place to buy a jet I was able to find some super small drill bits. The bit that fit in there snug was .029 according to my caliper measureing device thingy. So I used the next size up .031 and drilled out the accellerator pump nozzle. I cleaned it out when I was done ect. This is probably not a common practice but I figured what the hell. Got it back in and it seems worse if anything not better. Did I just not drill it out far enough? Do I need to buy a .034-.035 jet? How about the accelerator pump cam should I be messing with that? Thanks for any input this is my first time with any carb and first motor build
