The INEOS Grenadier was designed to be a serious, no-nonsense off-roader — the kind of vehicle that earns its keep in mud, mountains, and remote terrain rather than on a drag strip. Nobody expected a tuning company to find 80 extra horsepower hiding inside one, but that is exactly what Burger Motorsports has done.
A Rugged Off-Roader With an Unlikely Performance Secret
Burger Motorsports, a name long respected in the BMW aftermarket tuning community, has confirmed that its JB4 piggyback tuner is fully compatible with the INEOS Grenadier — and the power figures owners are reporting from real-world dyno runs are generating serious attention. According to Burger Motorsports, the JB4 delivers maximum wheel gains of 80 horsepower and 100 pound-feet of torque on the Grenadier, without touching the factory ECU programming.
The reason this is possible comes down to what sits under the Grenadier’s hood: a BMW-sourced B58 turbocharged inline-six, one of the most well-developed and tuning-friendly engines in the modern performance world. INEOS built a truck for the wilderness, but the engine it chose gave the aftermarket a wide-open door. Autoevolution covered Burger Motorsports’ confirmation of the tune, and the story it tells is one of unexpected crossover between hardcore off-road engineering and a decade of BMW performance expertise.
Why the BMW B58 Engine Changes Everything for Grenadier Owners
INEOS selected the BMW B58 turbocharged inline-six for the Grenadier — the same engine family that powers vehicles like the Toyota GR Supra, the BMW M340i, and the BMW X5 xDrive40i. That engine choice was made for reliability, refinement, and parts availability, but it came with an unintended consequence that Grenadier owners are now beginning to appreciate.
In tuning circles, the B58 has a well-established reputation for being conservatively mapped from the factory. The engine is physically capable of producing significantly more power than the stock tune unlocks, which is why it has become such a popular target for aftermarket development across multiple platforms. By the time the Grenadier arrived, companies like Burger Motorsports already had years of real-world data on how the B58 responds to boost increases, fuel adjustments, and timing changes.
For Grenadier owners, this translates into access to a mature, thoroughly tested tuning ecosystem that would normally take years to build around a niche vehicle. The JB4 for the B58-powered INEOS Grenadier is available directly through Burger Motorsports, and the foundation it rests on is anything but experimental.
What the JB4 Tuner Does — and Why the Approach Matters
The JB4 operates as a piggyback tuner, meaning it works by intercepting and modifying signals between the engine’s sensors and the factory ECU rather than overwriting the ECU’s software directly. In practical terms, the JB4 raises boost pressure and adjusts fuel and ignition timing signals in real time, effectively unlocking the power headroom the factory deliberately left unused — all while leaving the original ECU programming completely intact.
This distinction matters for several reasons. Because the factory ECU is never flashed or permanently altered, owners can disconnect the JB4 and return the Grenadier to a fully stock state at any time, leaving no permanent traces of modification. For owners concerned about warranty relationships, resale value, or simply wanting to experiment cautiously, this reversibility makes the JB4 one of the more pragmatic entry points into Grenadier tuning.
Burger Motorsports has confirmed the JB4 communicates correctly with the Grenadier’s specific engine management setup, meaning the unit is validated for this vehicle rather than being a generic B58 product repurposed for a different application. Burger Motorsports announced the Grenadier JB4 on Instagram, highlighting the 80 wheel horsepower and 100 wheel pound-feet of torque gains available to owners.
The Numbers: 80 Horsepower and 100 Pound-Feet of Measured Wheel Gain
The headline figures for the Grenadier JB4 tune are 80 wheel horsepower and 100 pound-feet of wheel torque. These are wheel figures — measured at the point where power is actually delivered to the road, after drivetrain losses have already been accounted for. Crankshaft figures, which are the numbers manufacturers typically advertise, are always higher, which makes these wheel gains particularly meaningful in real-world terms.
Owner-reported data adds further weight to those numbers. One user posting on The INEOS Forum documented results of approximately 400 horsepower and 500 lb-ft of torque on a stock Grenadier fitted with the JB4 piggyback from Burger Motorsports. That forum thread on ECU tuning and unlock options reflects a growing conversation among Grenadier owners exploring what the B58 platform is genuinely capable of delivering. Those output figures place a tuned Grenadier firmly in genuine performance SUV territory — a category the vehicle was never marketed to occupy.
For additional context on real-world B58 tuning behaviour across platforms, the broader enthusiast community has documented comparable gains extensively, giving prospective buyers a reliable baseline against which to evaluate these Grenadier-specific results.
What This Means on Road and Off It
On tarmac, 80 additional wheel horsepower meaningfully transforms the on-road character of a heavy-duty off-roader. Pulling out of junctions, merging onto motorways, and overtaking slower traffic all become noticeably more effortless. The Grenadier’s substantial kerb weight means it will never feel like a sports car, but the added output from the B58 closes the gap between capable workhorse and genuinely quick SUV in ways that daily drivers will notice immediately.
Off-road, the picture is equally interesting. The additional torque allows the Grenadier to push through difficult terrain in higher gears with less drama, reducing how frequently drivers need to drop down ratios in moderate conditions. Early owner reports suggest the power delivery remains smooth and progressive rather than harsh or aggressive — consistent with how the JB4 manages boost across other B58 applications.
The Grenadier’s drivetrain was engineered to handle serious off-road stress, which means it is generally considered well-suited to cope with elevated power at these gain levels. Owners should ensure they are running premium 91-octane fuel or higher when operating the higher-boost map, as the B58 performs best and most safely under increased load with quality gasoline. As with any tune, the modification places additional demand on the engine, turbocharger, and transmission, and warranty implications will vary depending on region and individual dealer relationships. Owners are advised to research their specific situation before purchasing.
The Grenadier’s Tuning Future Is Just Beginning
Burger Motorsports confirming JB4 compatibility with the Grenadier is not simply a product announcement — it is a signal to the broader aftermarket that this vehicle is a platform worth dedicating development resources to. As the owner community grows and shared dyno data accumulates across forums and social channels, prospective buyers will have an increasingly detailed picture of what long-term reliability looks like at elevated power levels. A dedicated video walkthrough of the JB4 installation and tuning process is also available for owners who want a closer look at the practical steps involved before committing.
There is a genuine irony at the centre of this story. INEOS positioned the Grenadier deliberately away from performance marketing, emphasizing utility, durability, and purpose-built engineering over horsepower figures. The BMW engine they selected to deliver on that promise is quietly making that positioning harder to sustain. For enthusiasts who want a vehicle that can genuinely go anywhere and still surprise a sports sedan at a motorway merge, the JB4-tuned Grenadier is shaping up to be a compelling and unconventional proposition — the kind of understated performance story the off-road world rarely produces. A dedicated video walkthrough of the JB4 on the Grenadier gives owners a closer look at the practical steps involved before committing.