Our development vehicle was a 2006 Toyota 4runner 4×4 with an automatic transmission.  The stock vehicle dynoed at 201 Rear Wheel Horse Power (RWHP). The basic kit, Stage I, put down 355 RWHP and retains OEM quality driveability. The system is completely silent in operation and still gets the same MPG as the stock 4Runner.

The key to producing this power level safely is in depth calibration work using highly advanced engine management and a properly configured fuel delivery system.  For engine management the kit uses the UCON Flex from iTronix Technologies.  This Advanced Engine Management System is self tuning with active dynamic air fuel ratio correction.  The UCON also has engine protecting engine guardian features.  If things start to go wrong the guardian features step in to protect the engine.  If the air fuel ratio deviates from the programmed value and the dynamic active fuel control cannot correct it, the guardian will depower the engine to protect it.  The guardian feature also steps in if the engine begins to overheat and we also program it to limit the maximum RPM until the engine is properly warmed up.

The fuel system includes a large 255 liter per hour fuel pump that is installed in the fuel tank and high flow fuel injectors that are more than twice the flow rate of the stock ones.  These upgrades are required to ensure a sufficient supply of fuel is delivered to the engine as commanded by the UCON Flex Advanced Engine Management System.

URD has chosen the highly efficient Rotrex C38-81 supercharger as the center of this supercharger system.  The Rotrex is most advanced supercharger design on the market today.  It features a small compact foot print with almost completely silent operation, with a very highly efficient traction roller drive system that will spin the turbo type impeller 7.5 times faster than the belt drive pulley is turned.  This high step up ratio and small diameter turbo style impeller brings boost in sooner than other more common types of centrifugal superchargers.  This gives you very nice off the line performance combined with unmatched top end power.  The Rotrex Supercharger features it own self contained oiling system using Rotrex\’ proprietary traction oil that is the key to the advanced traction drive system.

The air intake system brings in cool air from the stock location in the fender wall and into URD\’ custom high flow air filter box with a very large flat panel air filter for unrestricted flow into the supercharger. You can easily adapt it to your favorite snorkel system, but you may have a reduction in peak power with the added restriction to the intake.

The overall operation of the supercharger system is nearly completely silent, but we have added a turbo style blow off valve will announce that your 4Runner is indeed boosted.  When the throttle is suddenly closed when the engine is at high RPM like shifting gears with boost, the blow off valve will cycle with a very crisp note typical of high performance turbo systems.  It is always a crowd pleaser!