S68 JB4 Tuner for 2025+ BMW G90 M5 & G99 M5

S68 JB4 Tuner for 2025+ BMW G90 M5 & G99 M5Gains are 93whp on pump gas and up to 135whp on higher octane or E85 mixtures. The ultimate tune for your 4. 4L S68 powered G90 BMW M5. 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,

Gains are 93whp on pump gas and up to 135whp on higher octane or E85 mixtures.

The ultimate tune for your 4.4L S68 powered G90 BMW M5. 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 G90 S68 engine.

For Extra Ordinary Performance with JB4, We suggest buying Downpipe also.

No ECU flash needed and compatible with locked 🔒 ECUs

For the latest S68 performance results, updates, firmware, and map guide, be sure to visit Here

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. For more info on how to use the JB4PRO free app click here

S68 G90 M 5 JB4 FEATURES & BENEFITS

• Gains are 93whp on pump gas and up to 135 whp on higher octane or E85 mixtures.
• Improves 0-60 times and 1/4 mile times
• Preloaded with custom S68 ///M 5 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
• 5 year warranty

Vehicle Fitment

BMW M5
• 2025+ S68 G90 BMW M5
• 2025+ S68 G99 BMW M5 Touring

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 (computer) and manipulates vehicle performance through these connections making your vehicle much faster. While it's not the only tuning system that operates this way the JB4 separates itself from the competition with much more advanced connection points and processing, including CANbus, fuel & spark control, Bluetooth to your smartphone, and a variety of innovative and advanced features not possible with any other system. BMS regularly publishes free mapping and firmware updates adding performance and features as ongoing development allows. In addition, the JB4 system is not VIN-locked to your vehicle and can quickly be removed and swapped between cars or resold at a later time. Often imitated but never duplicated, the JB4 has been the gold standard in plug and play turbocharged performance tuning for over a decade.

Is the JB4 a real tune?

Yes the JB4 is a real tune. By tapping into specific sensors and CANbus for real time vehicle data the JB4 is able to alter your boost, timing, AFR, and/or fuel trims, to a similar degree an ECU reflash would, but without the vehicle ever knowing its been tuned. The result is safe, smooth, and significant power and torque gains while retaining your factory safety systems and without having to unlock/flag your ECU.