Originally Posted by Newtons3
Before you even begin on the carburetor check the motor for vacuum leaks and proper timing adjustment.
1.st verify float level. 2. Verify properly operating/adjusted accelerator pump. 3. Check power valve.
All of these suggestions assume your carburetor is clean and in good shape.
I would contact Holley and find out which jets are supposed to be in it for your application.
Float? Could be. The vacuum port for the vacuum distributor should be on teh carb ABOVE the throttle plate/shaft.
What's your ignition timing set at with the vacuum disconnected? At least 12* BTDC?