The Horse B20 engine takes a different approach to off-road performance. Rather than focusing primarily on acceleration or exhaust sound, the new 2.0-liter turbocharged four-cylinder is designed to keep running while submerged in up to 43 inches (1.1 meters) of water.
Horse B20 Engine Is Built for Deep Water
Horse Powertrain, the UK’s low-emission hybrid supplier, says the B20 produces 248 horsepower and 280 pound-feet of torque. While those figures are not the engine’s main selling point, its sealed construction is designed specifically for demanding water-fording situations.
Horse Powertrain claims the B20 carries an IPX8 rating, meaning it is protected against continuous submersion in water deeper than 1 meter. The company says the engine can operate without problems in 43 inches (1.1 meters) of water.
That capability applies to the engine itself, however, and does not mean a vehicle’s door seals can prevent water from entering the cabin while crossing a moving river.
How the B20 Stays Watertight
Horse Powertrain says keeping the B20 sealed required a fully enclosed structure with torsional vibration dampers and dedicated seals between the engine and transmission. Its electrical components and sensors are also IPX8-rated and continuously monitor the engine’s operating environment.
The control system can automatically adjust the engine when it is submerged, using sensor feedback to limit power or modify throttle response.
“When the engine is submerged in water, the control system makes automatic adjustments such as limiting power or adjusting the throttle response, based on feedback signals from the sensors.”
The B20 was first showcased at the 2026 Beijing auto show as part of a plug-in hybrid powertrain in the Geely Galaxy Cruiser 700 off-road vehicle. The vehicle is available in China only and uses Horse’s three-speed hybrid transmission.
Engine Designed for Off-Road and Hybrid Applications
Beyond its water-fording capability, Horse Powertrain says the direct-injected B20 can propel an off-road SUV or pickup truck up a 45-degree grade. The engine weighs 287 pounds and can also serve as a range-extending generator for a battery-electric vehicle.
The B20 uses an advanced version of the Miller combustion cycle, allowing it to achieve a brake thermal efficiency of 48.4%. Horse Powertrain says the technology is intended to improve emissions and fuel economy.
“The Horse B20 demonstrates how we are meeting the full range of market needs, delivering flexible engine and powertrain solutions designed for multiple use cases and applications,” said Ingo Scholten, Deputy Chief Technology Officer of Horse Powertrain.
Additional B20 Engine Technology
The B20 also incorporates high-tumble intake ports and pistons designed to support a cleaner and faster combustion event. The engine’s combination of efficiency, hybrid compatibility and water-fording capability gives the design several potential applications.
With battery-electric vehicles facing an uncertain future, particularly in the US, the article notes that internal-combustion engines will need to become more efficient, cleaner-burning and capable across multiple use cases. Water fording is identified as one such application, especially as flooding becomes a serious problem in many parts of the world.
Horse Powertrain’s Newest Engine
Horse Powertrain was technically established as a new company in 2024 under the Geely umbrella, although it has older roots with Renault. The B20 is the latest engine from the company, which has a growing portfolio of efficient and powerful powertrains.
