Holley 80457-2 stumble

I have an off idle hesitation on a holley 600 I just installed.

Vehicle: 78 Dodge Power Wagon 318 4-speed 3.55 gears completly stock bought off the original owner 79K miles.

I bought the truck last summer, rebuild the stock BBD Carter and run it all winter. Started right up idled fine even afters sitting for weeks at a time but it was lazy in the mid range.

Just put on a LD4B intake and a used 600 carb that I also rebuilt, but was so clean inside that it did not need it.

It has an off idle hesitation, enough to where I know my wife will not drive it, it also hesitates at part time throttle.