JB4 Tuner for 2021+ Toyota GR Yaris & GR Corolla Turbo

Power gains of up to 50whp and 60wtq to the wheels on a stock vehicle without the risks associated with flashing! The JB4 is a plug and play performance tuner that attaches to two easy to access sensors in the engine bay and works with your factory DME 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. JB4 Installation is very discrete and it quickly removes without a trace when needed.

Fuel economy during normal driving is unchanged. Compatible with all driving modes. Does NOT require flashing the ECU! The system is fully CANbus equipped allowing the tuning to take in advanced engine data for mapping, logging, and diagnostics.

Data channels include boost, timing, air/fuel, fuel trims, throttle, knock control, and much more! Made in the USA. 5-Year warranty. Wirelessly Connect to your JB4: Grab our all-new JB4 PRO smartphone connection to wirelessly connect the JB4 tuner to your Bluetooth 4.0 compatible iOS or Android device.

This option allows you to record and analyze vehicle and tuning data, change JB4 performance maps, and update JB4 firmware as we release free newer versions with updates, more powerful maps, and new features under development. Our new adapter fits fully inside the JB4 enclosure for enhanced weather protection and a more streamlined look.

The JB4PRO Free app features an intuitive easy-to-use interface, help buttons, and advanced log analysis tools that can estimate the performance of your car and help identify any tuning concerns.

Vehicle Fitment

• Toyota
• 2021+ Toyota GR Yaris Turbocharged 3cyl
• 2023+ Toyota GR Corolla Turbocharged 3cyl