Power gains of up to 30hp and up to 68Nm on a stock vehicle

Ready to take your 2021+ Range Rover 2.0L Turbo to the next level? How does up to 30hp to the wheels sound? More horsepower means better throttle response, faster acceleration, and more fun while keeping normal driving and gas mileage unchanged.

The JB4 features a simple plug and play installation harness for easy installation and includes many features not found on any other tune. Including the ability to enable/disable the tuning from the driver’s seat, gear-dependent boost control to help with traction, E85 compatibility, built-in diagnostic code reading/deleting, expanded engine safety systems, free firmware updates, in dash boost gauge, the ability to control the exhaust flapper using your BC button, and much more.

The JB4 does not require any additional modifications or previous stages. Simply install the JB4 as your first and only modification and enjoy an entirely new fast and smooth racing experience.

The JB4 is a full plug and play device that installs and removes in minutes at home without special tools and unlike flash maps that permanently write over your DME with the JB4 your DME is never aware it’s running more than the factory power levels. And when you’re ready to change things up the JB4 is not VIN locked and can be moved to your next vehicle or resold.

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.

Range Rover JB4 Features & Benefits

• Power gains of up to 30hp and 50tq to the wheels on a stock vehicle
• Improves 0-60 times and 1/4 mile times
• Preloaded with custom JB4 Range Rover 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 different 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 unrivalled 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 aluminium enclosure for protection
• Made in the USA
• 5-year warranty

Vehicle Fitment

Range Rover (P250 and P300 Engines)

• 2021-Present Land Rover Defender

What is a JB4?

The JB4 is a plug-and-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.