In order to achieve the maximum potential from a turbocharged engine, it is necessary to control the boost levels. The EVC units provide immediate push button selection of preset levels of boost pressure, plus a return to factory boost level, by switching the EVC units off. All boost selections and adjustments are accessible from within the cockpit of the vehicle, which gives the driver the ability to change boost pressure on the fly. Aided by fuzzy logic, the EVC also possesses the ability to learn the vehicles boost pressure curve. This learning feature allows a maximum reduction in turbo lag without overboosting.