McLaren JB4 Performance Tuner for M838T Engines - Burger TuningInstant Horsepower and Torque Gains The JB4 is a plug and play McLaren tuner that plugs into easy to access sensors in the engine bay and works with your factory ECU tuning to remap your boost, timing, and fueling for optimal performance and reduced turbo lag. It features a 64mhz processor allowing sensors to be sampled 800 times per second using dedicated 10 bit digital to analog converters, ensuring smooth and powerful performance. No ECU flash