FACTORY PART
555537 Main Jet Kit (Alcohol) contains 1 Alcohol main fuel nozzle, 1 BHA alcohol needle and 1 DID Gas needle, .38 - .40 - .42mm Pilot / idle jets. Also contains 1.35 - 1.37 - 1.42mm main jets. Switching to Methanol is the easiest way to make 10% more horsepower. However, there is slightly more maintenance when using methanol.
*for reference, please refer to Racing Performance Catalog & Reference Guide on the Briggs & Stratton website