S58 JB4 BMW X3M X4M Performance Tuner

OVERVIEW

The JB4 takes your S58-powered X3M or X4M from bone stock to full-race-ready with room to grow along the way. It taps into the car's sensors and CANbus for real-time control, giving you user-adjustable 1st and 2nd gear boost limiting, electronic wastegate control, and E85 support, all through simple smartphone integration. Installation and removal are completely clean, with no cutting or splicing of factory wiring.

SPECS

• Meaningful power gains on pump gas, with further headroom on higher octane or E85 blends
• Improves 0-60 and quarter-mile times
• Includes multiple tuning maps for different fuel types and modification levels
• Quick plug-and-play installation with zero permanent modifications
• Supports E85 ethanol blends
• Reads and clears engine fault codes
• Displays and logs up to 40 real-time engine parameters
• Boost-by-gear control for improved traction off the line
• Controls exhaust flap operation on supported vehicles
• Compatible with the free JB4PRO smartphone app
• Full CANbus integration for factory-level communication with the DME
• No impact on fuel economy during normal, non-aggressive driving
• Requires 91 octane or better for performance gains
• Not VIN-locked — fully removable and can be resold or moved to another car
• Housed in a rugged billet aluminum enclosure; designed and assembled in the USA
• Backed by a 5-year warranty

PARTS INCLUDED

• 1x JB4 (or JB4PRO) tuner unit in billet aluminum enclosure
• Plug-and-play installation harness

TECH RESOURCES

• 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 new versions release with more powerful maps and features

PART NUMBER

• BMS-JB4-BMW-S58-XXM

VEHICLE APPLICATIONS