Power gains of up to 80WHP and 100WTQ on a stock vehicle without the risks of flashing!

The JB4 tuner for the B58 powered INEOS Grenadier is the most advanced plug & play tuning system available for the 3.0L turbocharged engine platform. Power gains of up to 80 horsepower and 100 lb-ft of torque at the wheels are possible on a completely stock Grenadier running pump gas. Vehicles equipped with bolt-on upgrades, higher octane fuel, E85 mixtures, or larger turbochargers can see even greater gains. 

No ECU flash needed and compatible with locked 🔒 ECUs

The JB4 features a simple plug & play installation harness for fast installation and removal while offering advanced tuning features not available with other tuning systems. These include in-dash map switching between stock and performance maps, optional in-dash boost gauge display, boost limiting by gear for improved traction, progressive water/methanol integration, built-in data logging, fault code reading and clearing, optional electronic wastegate control to prevent throttle closure with exhaust modifications, exhaust flapper control, and many additional features.

Unlike many expensive tuning solutions, the JB4 does not require additional stages or supporting modifications. Simply install the JB4 as your first upgrade and immediately experience improved power delivery, smoother acceleration, and stronger turbo performance.

The JB4 requires no manual setup for basic operation. However users who want to adjust maps, log engine data, or access advanced tuning features can add one of our optional Bluetooth smartphone adapters.

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.

JB4 Map Guide:

Map0: Stock tuning – JB4 disabled
Map1: +3psi over stock (91 octane)
Map2: +4psi over stock (91–93 octane)
Map3: +6psi over stock (93+ octane)
Map4: +8psi over stock (Race gas or 30% E85)
Map5: +10psi over stock (Race gas or 30% E85)
Map6: Custom tuning map
Map7: Progressive water/methanol map
Map8: Valet / Low boost mode

This B58 JB4 model is compatible with all GEN1 and GEN2 B58 motors. For the newest B58TU2 GEN3 motor refer to this product page.

JB4_B58 is CARB Approved Under Executive Order (EO) No.D-744-4 for all 2016-2018 BMW 230i, 330i, 430i, 530i, 340i, 440i, 740i, M240i, and X1 applications.

JB4 Power Gains, Features, & Benefits

• Up to 80hp and 100 lb-ft torque gains on a stock INEOS Grenadier
• Includes multiple tuning maps for different fuel types.
• Quick plug and play installation.
• Supports E85 ethanol blends.
• Reads and deletes fault codes.
• Displays and logs up to 40 engine parameters.
• Boost by gear control for improved traction.
• Controls exhaust flap operation on supported vehicles.
• Compatible with the free JB4PRO app.
• Offers better performance and safety than basic chip tunes.
• Full CANbus integration.
• Runs as smoothly as stock.
• Compatible with all driving modes.
• No impact on fuel economy during normal driving.
• Requires 91 octane or better for performance gains.
• Not VIN locked and fully removable.
• Includes billet aluminum enclosure.
• Designed and assembled in the USA.
• 5-year warranty.

Vehicle Fitment

2023+ INEOS Grenadier 3.0L B58 SUV
2023+ INEOS Grenadier Quartermaster 3.0L B58 Pickup

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 the 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 and is sold in over 67 countries worldwide.

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.

California Customers -- Download the CARB Version Installation Guide

Stock vs JB4 Dyno Results

BMW B38/B46/B48/B58 JB4 Install Videos