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 G87 M2, G80 M3, or G82 M4, 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, smartphone integration, electronic wastegate control, ethanol fuel support, and built-in advanced CANbus-based diagnostic tools. Installation is easy and completely removable with no splicing or cutting of factory wires making the JB4 an excellent choice for your S58 engine.

Also available with our new JB4PRO board which includes built in Bluetooth, fuel pressure control for more advanced tuning with ethanol mixtures, built in flex fuel/port injection/WMI control using our PNP add on harness, onboard data-logging memory, and many additional features to be unlocked in the future via free firmware updates.

• Optional: For Extra Ordinary Performance with Jb4 We also recommend Our S58 Downpipe

Includes the JB4PRO app! Wirelessly connect the JB4 to your iOS or Android device 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.

The JB4PRO 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. More information on the JB4PRO app is available here.

S58 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 S58 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 20 different gauges/engine parameters in real-time with the JB4PRO app.
• Boost by gear in 1st, 2nd, and 3rd can be controlled via the JB4PRO app for a perfect launch
• Compatible with the FREE JB4PRO app 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
• Designed and assembled in the USA
• 5 year warranty

S58 JB4 Vehicle Fitment

• 2023-Present S58 G87 BMW M2
  
• 2021-Present S58 G80 BMW M3
  
• 2021-Present S58 G80 BMW M3 Competition
• 2021-Present S58 G82 BMW M4
• 2021-Present S58 G82 BMW M4 Competition
• 2023-Present S58 G82 BMW M4 CSL
• 2022-Present S58 G83 BMW M4 Convertible  

What is a JB4?

The JB4 is a plug & play tune available for turbocharged vehicles. The JB4 tuner installs between your car's sensors and its DME/ECU and manipulates vehicle performance through these connections making your vehicle much faster. The JB4 separates itself from the competition with more advanced connection points and processing, including CANbus, fuel & spark control, Bluetooth connectivity, and a variety of innovative and advanced features. The system is not VIN-locked and can quickly be removed, swapped between cars, or resold later.

Is the JB4 a real tune?

Yes. By tapping into specific sensors and CANbus for real-time vehicle data the JB4 can alter boost, timing, AFR, and fuel trims similar to an ECU reflash, while retaining factory safety systems and without unlocking or flagging the ECU.

DYNO

G80 M3 JB4 Dyno, 30% E85 fuel, JB4, BMS S58 Intake