Supercharger and Induction System

The induction system consists of induction tubes, throttle body, and a Roots style supercharger with an integral intake manifold and intercooler. A forward section to the induction system consists of a central intake port that splits into twin thin wall cast aluminum induction tubes. Each tube incorporates a silencer in order to reduce induction noise without disrupting air flow. After each silencer a flexible port duct connects to the rear tube that combines the air flow into a single port at the rear of the engine. A flexible port duct connects the rear tube to the 80 mm (3.15 in) diameter throttle body mounted at the rear of the supercharger.

The throttle body is an electronic throttle controlled (ETC) design. The throttle body, EVAP purge valve solenoid, and bypass actuator cable mount to the supercharger bypass valve.

The supercharger pulley is driven by a serpentine drive belt. The pulley drives the supercharger from the front of the engine. The two tri-lobe helical Roots type rotors are counter-rotating as the drive and driven rotors are geared to each other. The rotors are mirror image, precision hobbed aluminum extrusions rotating on press-fit steel shafts. Ball bearings between the gears and the rotors support the rotors at their forward end. The forward bearings are lubricated and cooled by a volume of synthetic gear lubricant contained within the supercharger front cover. At the rear, sealed maintenance-free needle bearings support the rotors. The incoming air enters the rotor chambers at the lower rear just past the bypass valve. Air is pushed up around the outside of the rotors and is expelled from the rotors at the upper front of the supercharger body. Mounted on top of the supercharger body is the intercooler housing. The air flows up from the supercharger and travels through the intercooler tube fins and then down into the individual cylinder inlet runners. The supercharger displacement and pulley ration are proportioned to deliver almost two times the volume of air the engine would naturally aspirate, providing positive manifold pressure when the valve is closed. The bypass valve controls recirculation between the rotor outlet and inlet to reduce parasitic losses and noise during light load operation, at which time the valve is open.

The intercooler housing contains four longitudinal bores that house the four cylindrical intercoolers. The manifolds at the front and rear of the intercooler housing route the coolant through the interior of the four intercooler tubes. A coolant fill cap is located on the top of the intercooler housing. Slots in the intercooler housing direct the supercharged air flow past the fins of the intercooler tubes. Once cooled by the intercooler the supercharged air is directed through the top of the intercooler housing and down into the outboard sides of the intercooler housing and into individual runners that proceed through the supercharger housing and into the cylinder head intake runners. Inputs from multiple sensors for vacuum and pressure and a temperature sensor are used by the engine management system to control the supercharge operation. The bypass valve for the supercharger is operated through a cable by a supercharger bypass valve actuator. The supercharger bypass valve actuator is operated by supercharger pressure and vacuum operated by a charge air bypass regulator solenoid valve. The charge air bypass regulator solenoid valve is controlled by input from the engine management system. A cooling system separate from the engine cooling system is used for the intercooler. An electric remote-mounted coolant pump is used to circulate the coolant between the intercooler of the supercharger and the heat exchanger mounted at the front of the vehicle.