Description
The Burger Tuning JB4 Tuner for the 2025+ Land Rover Defender OCTA 4.4L V8 Twin Turbo unleashes phenomenal power gains with up to 125 wheel horsepower on pump gas and as much as 260whp on higher octane fuels or E85 mixtures. Designed specifically for the OCTA V8 powerplant, this tuner is your key to transforming the Defender from stock performance to full race-level power — with precise control every step of the way.
Installation is simple with a plug & play harness — no cutting or splicing required — and completely reversible. The JB4 includes exclusive features like user-adjustable boost limiting by gear, electronic wastegate control, and full CANbus-based diagnostics to keep your engine safe and performing optimally. Compatible with locked ECUs, no ECU flash is required.
The JB4 offers wireless connectivity via smartphone apps including the industry-leading JB4 Mobile and the all-new JB4PRO app, allowing you to switch maps on the fly, monitor over 40 engine parameters in real time, and update firmware with free upgrades for new features and performance enhancements.
Features & Benefits
- Gains of up to 125whp on pump gas and up to 260whp on high octane/E85
- Improves acceleration — faster 0–60 mph and quarter-mile times
- Preloaded with custom JB4 OCTA tuning software and 8 performance maps
- Full E85 ethanol fuel compatibility for flexible tuning options
- Reads and deletes fault codes to keep your Defender running clean
- Monitors and logs up to 40 engine parameters with the JB4 app
- Boost-by-gear control for 1st, 2nd, and 3rd gears via smartphone app
- Easy plug & play installation — no wiring modifications necessary
- Advanced CANbus OBDII integration for seamless ECU communication
- Runs as smooth as stock with factory drivability and all driving modes supported
- No fuel economy penalty under normal driving conditions
- Requires 91 octane or better for maximum performance
- Not VIN locked; JB4 can be removed and resold without trace
- Durable billet aluminum enclosure protects the tuner
- Proudly Made in the USA with a 5-year warranty
Vehicle Fitment
Land Rover
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2025+ Land Rover Defender OCTA 4.4L V8 Twin Turbo
What is a JB4?
The JB4 is the most advanced plug-and-play tuner designed for turbocharged vehicles. Installed between your vehicle’s sensors and ECU, it precisely controls boost, fueling, and ignition timing for major power gains without sacrificing safety or reliability. Unlike flash tuning, the JB4 is fully reversible, not VIN-locked, and supports wireless smartphone connectivity. With frequent free firmware and map updates from Burger Motorsports, it remains the gold standard in turbocharged vehicle tuning for over a decade.
