Gains are 80whp/100wtq on pump gas and up to 150whp/175tq on higher octane or E85 mixtures.

The ultimate tune for your S58 powered vehicle, the JB4 allows you to go from factory stock to full race and everywhere in between. The JB4 installs and removes easily and includes many unique features not found in any other tune, including user-adjustable 1st and 2nd gear boost limiting, electronic wastegate control, smartphone integration, ethanol fuel support, and built-in advanced CANbus-based diagnostic tools. Installation is completely removable with no splicing or cutting of factory wires.

Wirelessly connect the JB4 to your Bluetooth 4.0 compatible iOS and Android device via the JB4 Mobile connect kit, or to your Windows laptop with the BMS data cable. Both options allow 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. A separate JB4 Mobile app purchase is also required.

JB4 Features & Benefits

• Gains are 80whp/100wtq on pump gas and up to 150whp/175wtq on higher octane or E85 mixtures.
• Improves 0-60 times and 1/4 mile times
• Preloaded with custom JB4 tuning software and up to 8 maps for various fuel and modification levels
• Ethanol (E85) compatible tuning maps
• Able to read/delete fault codes
• View and record up to 40 gauges/engine parameters in real-time with the JB4 app.
• Boost by gear in 1st, 2nd, and 3rd can be controlled via the JB4 app for a perfect launch
• Compatible with JB4 Mobile for smartphone logging, tuning changes, and adjustment
• The JB4 offers a lot more performance, functionality, and safety than your average performance chip
• Quick Plug & Play Installation
• CANbus OBDII integration offering unrivaled tuning features and performance
• Improved performance over non-integrated chip tunes
• Runs as smoothly as stock. This is how your vehicle should have come from the factory
• Compatible with all driving modes
• Fuel economy unchanged during normal driving
• 91 octane fuel or better required for performance gains
• Not VIN locked and can be removed without a trace and resold down the road
• Includes the rugged JB4 billet aluminum enclosure for protection
• Made in the USA
• Free USA Shipping
• 5 year warranty

S58 JB4 Vehicle Fitment

BMW X3M
• 2020-Present S58 F97 BMW X3M
• 2020-Present S58 F97 BMW X3M Competition

BMW X4M
• 2020-Present S58 F98 BMW X4M
• 2020-Present S58 F98 BMW X4M Competition