The engine revs louder and louder as it approaches its redline. Your tuner sits in front of the computer calibrating the MegaSquirt ECU to its fullest potential, maxing out both the horsepower and torque curve of your engine. MegaSquirt is an aftermarket EFI (electronic fuel injector) built to work on internal combustion engines. EFI controllers allow you to tune your car and achieve the best performance possible for your engine. Since 2001, MegaSquirt has introduced 8-bit and 16-bit processors along with systems capable of handling data speeds up to 50 MHZ. ECU tuning on a MegaSquirt controller is done either on the road or on a Dynamometer. MegaSquirt is an open source system that leaves much room for additional features. You can even build the printed circuit board yourself. The MegaSquirt controller customizes how and when the car's computer engages the throttle position, IAT, IAC sensors, and fuel pump. There is a vast inventory of MegaSquirt controllers available on eBay. Tune your MegaSquirt system to run your car at its maximum potential.