Another great tuning kit from Holley. This one will allow you to tailor accelerator pump performance to the engine's actual requirements. Each cam has a different shape or profile to give different results. Cam lift directly affects the accelerator pump stroke and, therefore, pump capacity. Ramp profile or shape controls the timing of the shot. A steeply-rising ramp shape will give a fast, heavy fuel shot right off idle. Conversely, a gentle sloping ramp will spread the pump action over a longer period of time.