Unlock serious, safe power from your BMW S58 with the JB4 plug and play tuning system. Tailored for the 2021+ G80 M3, G82 G83 M4 and 2023+ G87 M2, this proven piggyback ECU delivers gains of around 80whp/100wtq on pump fuel and up to 150whp/175wtq on higher octane or E85 blends. Supplied by Nforcd in the UK, every unit now includes the free JB4PRO app for effortless wireless control, map switching and data logging.
- Plug and play S58 tuning box with advanced CANbus integration for smooth, stock-like drivability
- Preloaded with S58-specific software and up to 8 selectable maps for different fuels and modification levels, including ethanol blends
- Boost by gear control in 1st, 2nd and 3rd to help maximise traction and improve 0 to 60 and quarter mile times
- Read and clear fault codes, plus view and log up to 20 live engine parameters via the included JB4PRO smartphone app
- Optional JB4PRO board adds built-in Bluetooth, fuel pressure control, onboard logging memory and integrated flex fuel, port injection and WMI control with plug-in add-on harnesses
- Fully removable, not VIN locked and designed for quick installation with no cutting or splicing
Vehicle fitment
- BMW M2 G87 2023+ S58
- BMW M3 G80 2021 to 2026 including Competition
- BMW M4 G82 2021+ including Competition and CSL
- BMW M4 G83 Convertible 2022+
The JB4 is a genuine tuning solution for turbocharged BMWs, altering boost, timing, AFR and fuel trims while retaining factory safety strategies. It works with all driving modes and offers more features than typical chip tunes. Optional flex fuel and port injection harnesses, plus an extension harness to simplify access to the lower MAP sensor, are available separately. Designed and assembled in the USA with a 5 year warranty.
Order your S58 JB4 from Nforcd today. Professional fitting is available at Nforcd in Warwickshire. To request a fitting quote, email Sales@nforcd.com.