Finally an upgrade kit that adds a high fuel pressure connection to the JB4 for B58/B48 Gen2 and S58 platforms allowing direct control of fuel pressure and fuel trims. Most useful for manual transmission vehicles or those running heavy E85 mixtures on a locked ECU.

It's easy to install and includes a replacement JB4 board and a fuel pressure connector harness that attaches to your existing JB4 harness.

Note this kit is not compatible with Gen1 B58 motors.

Customers who purchased their JB4 new from Palenon Performance can receive a $75 core refund for their original JB4 board. To take advantage of this core refund ship your original board along with copies of the original JB4 purchase receipt and your JB4 upgrade kit order number to the address on our website. Cores must be received 45 days after upgrade kit receipt to qualify.

For installation directions and additional information click here.

Vehicle Fitment

BMW 2 Series
• 2022+ B58 G42 BMW M240i, M240i xDrive, and M240xi
• 2023+ S58 G87 BMW M2
• 2022+ G42 B48 BMW 220i, 230i
• 2020-2021 F22 F23 B48 BMW 230i including xDrive
• 2020-2021 F22 F23 B48 BMW 225i including xDrive

BMW 3 Series
• 2019+ B58 G20 G21 BMW M340i, M340i xDrive, and M340xi
• 2021+ S58 G80 BMW M3
• 2021+ S58 G80 BMW M3 Competition
• 2020+ G20 G21 B46 B48 BMW 318i, 320i, 320Li, 320e, 330i, 330e, 320Li including xDrive

BMW 4 Series
• 2021+ B58 G22 G23 G26 BMW M440i, M440i xDrive, and M440xi including Gran Coupe
• 2021+ S58 G82 BMW M4
• 2021+ S58 G82 BMW M4 Competition
• 2022+ S58 G83 BMW M4 Convertible
• 2021+ G22 G23 G26 B48 BMW 420i, 430i including Gran Coupe and xDrive
• 2020 F32 F33 F36 B48 BMW 430i including Gran Coupe and xDrive
• 2020 F32 F33 F36 B48 BMW 425i including xDrive

Toyota Supra
• 2020-2026 Toyota GR Supra Mk5 B58 3.0L 6 cyl.
• 2020-2026 Toyota GR Supra Mk5 B48 2.0L 4 cyl.