JB4 BMW B58 Gen3

OVERVIEW

The JB4 for BMW's Gen 3 B48/B58 engines is a plug-and-play tuner delivering up to 100whp (125hp crank) on a completely stock car running 93 octane, with even higher gains on ethanol blends. It's built to process the newer generation's ultra-fast SENT digital sensor signals in real time with zero latency.

SPECS

• Up to 130hp gains at the wheels on a stock vehicle
• On-the-fly in-app map switching, boost-by-gear control, progressive water/methanol support, built-in data logging and fault code reading
• Supports E85 ethanol blends; full CANbus integration
• Compatible with the free JB4PRO app (Bluetooth 4.0, iOS/Android) for live data, map changes, and firmware updates
• Displays and logs up to 40 engine parameters
• Not VIN-locked and fully removable; includes billet aluminum enclosure
• Designed and assembled in the USA; 5-year warranty
• 91 octane or better required for performance gains

PARTS INCLUDED

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

TECH RESOURCES

• Simple plug-and-play installation harness — install as your first and only modification, no staged upgrades required
• Important: this unit fits only the exact Gen 3 B48/B58 vehicles listed below — it does not plug into earlier-generation B48/B58 engines due to different connectors. Verify fitment carefully before ordering, as incorrect orders are subject to a restocking fee
• Install guide: Gen 3 B48
• Install guide: Gen 3 B48 (Transverse)
• Install guide: Gen 3 B58

VEHICLE APPLICATIONS