JB4 Tuner for 2016-Present Ford Focus RS & ST - Burger TuningPower gains of up to 50whp and 60wtq to the wheels on a stock vehicle The JB4 is a plug and play Ford Focus RS 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