Land Rover Defender OCTA 4.4L V8 Twin-Turbo JB4 Tuning Box

The JB4 tuning box for the 2025+ Land Rover Defender OCTA 4.4L V8 twin-turbo delivers real, reversible gains without ECU flashing or wiring cuts. Plug-and-play fit in under an hour.

• Up to 125whp on 91+ octane, 260whp with E85 or high-octane blends
• OCTA-specific preloaded maps, 8 selectable tunes, boost-by-gear (1st-3rd)
• Real-time logging + 40 live gauges via JB4PRO app (Bluetooth adapter sold separately)
• Read/clear fault codes, CANbus OBDII integration, electronic wastegate control (in development)
• Fully removable, not VIN-locked - move it, resell it, or upgrade later
• Rugged billet aluminium housing, made in USA, 5-year warranty