How-to adjust the accelerator pump on Holley carburetors to avoid stumbling and hesitation upon acceleration. Tips include: How to check for the clearance between the accelerator pump diaphragm arm & operating lever; how-to select the correct accelerator pump nozzle size, and accelerator pump cam selection and installation. Additional information can be found on Holley's website: http://forums.holley.com/entry.php?428-How-To-Cure-Carburetor-Stumble