Won't Start need advice, Please read....

I agree w/ post #39, assuming it ran fine and at an acceptable speed (<1000 rpm) when you goosed the throttle. There is no way a rebuilder could set the idle speed screw predictably.

If it will only idle at excessive speed (>1000 rpm), you may have an intake vacuum leak or the carb's "idle circuit" may be bad. This is a common problem with the Holley 1920 and since it has a sealed metering block, most rebuilders don't touch that part.