Stock accelerator pump covers permit only a 60% - 70% fuel charge in the pump chamber. Turn the throttle and air trapped in the chamber is compressed disrupting fuel delivery. All the while tuning the squirt means a complicated change of the leak jet. The Result: Hesitation, bog and a tuning headache. The Patented Boyesen QuickShot 3's triple effect: 1. Completely fills the pump chamber with fuel 2. Eliminates troublesome air and 3.Provides an adjustable leak jet circuit for simple hand tuning.