Horse Powertrain reveals waterproof hybrid engine for off-road vehicles

9 September 2026

Horse Powertrain has revealed its “fully waterproof” engine, the Horse B20. Designed for extreme off-road vehicles and deep-water wading, the Horse B20 is intended to brings all-terrain capabilities to hybrid vehicles, including applications for SUVs and pick-up trucks.

Compliant with the IPX8 waterproofing rating, as defined by the International Electrotechnical Commission standard IEC 60529, the Horse B20 engine can operate up to depths of 1.1 meters. It is also capable of maintaining continuous power output under extreme off-road high-load conditions including 100% grade (a 45° incline) climbing.

Weighing just 130 kg, the Horse B20 is a four-cylinder, 2-liter inline gasoline engine designed for HEV, PHEV, and REEV applications meeting China 6b emission standards. Featuring a turbocharger and direct injection (GDI) technology, it can output up to 140-185 kW of power and 300-380 Nm of torque. The engine utilizes a Miller cycle valve timing, enabling a brake thermal efficiency of 48.4%, according to Horse Powertrain.

The Horse B20 features a range of features to encourage leaner, cleaner combustion and to maximize fuel economy and range. These include high-pressure injectors and high-tumble intake ports, which promote superior air-fuel mixing and more efficient combustion. Additionally, the engine features pistons designed to make full use of the “squish” effect to promote air-fuel mixing at the peak of the compression cycle—this enables the spark plug to ignite a cleaner and faster combustion event.

The engine uses a gantry-type aluminum block with integrated exhaust manifold and a simplified balance shaft system, which improve NVH, durability, and overall efficiency. It also features a variable displacement oil pump ensuring optimal oil flow and pressure throughout the engine.

To improve the cooling efficiency, an exclusive fully active dual-cooling system ensures the unit remains in the optimal operating temperature, even under extreme conditions such as continuous slope climbing and long-duration, high-temperature scenarios.

To achieve the IPX8 waterproof rating, the engine uses a fully sealed waterproof structure equipped with torsional vibration dampers and dedicated engine-transmission sealing. Fitted with IPX8-rated electrical components and sensors, it continuously monitors the surrounding operating environment of the engine. 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. This ensures stable operation of the engine under deep wading conditions.

First showcased at the Beijing Auto Show 2026, the Horse B20 was recently used within a PHEV powertrain in the Geely Galaxy Cruiser 700 off-road vehicle (China only), paired with a Horse 3DHT230, a 3-speed intelligent hybrid transmission.

Source: Horse Powertrain