HORSE B20 Engine Adds Waterproofing for Extreme Off-Road Use

London, UK (8 September 2026) – Horse Powertrain has revealed the HORSE B20 engine, a fully waterproof four-cylinder gasoline power unit developed for hybrid vehicles operating in extreme off-road conditions and deep-water wading. Designed for SUVs and pick-up trucks, the engine is intended to maintain continuous and stable power under high-load conditions, including 100% grade climbing. Its powertrain is fully waterproofed to IPX8 standards and can operate at depths of up to 1.1 meters. The HORSE B20 weighs 130kg and supports HEV, PHEV, and REEV applications, combining off-road capability with a focus on combustion efficiency, durability, and fuel economy.

HORSE B20 Powertrain Specifications

The HORSE B20 is a 2-liter inline four-cylinder gasoline engine with turbocharging and direct injection. It delivers 140-185kW of power and 300-380Nm of torque, while an advanced Miller cycle enables brake thermal efficiency of 48.4%. Horse Powertrain says the engine is designed to support multiple hybrid powertrain configurations, giving vehicle manufacturers flexibility across different applications. Its compact 130kg weight also supports integration into SUVs and pick-up trucks where power, packaging, and operating durability are important. The combination of turbocharging, direct injection, and the Miller cycle is intended to provide strong output while improving combustion efficiency and fuel economy.

Combustion Efficiency Technologies

Several combustion technologies are designed to support leaner and cleaner operation. High-pressure injectors and high-tumble intake ports promote improved air-fuel mixing, helping the engine achieve more efficient combustion. The pistons are also designed to make full use of the “squish” effect during the peak of the compression cycle, promoting further air-fuel mixing before ignition. This allows the spark plug to initiate a cleaner and faster combustion event. Together, these features support the engine’s stated focus on fuel economy and range while retaining the power and torque needed for demanding hybrid applications. The approach is particularly relevant when the engine is subjected to sustained loads during off-road operation.

Engine Durability and Thermal Management

Horse Powertrain has also incorporated several technologies outside the cylinders to improve efficiency, durability, and refinement. A gantry-type aluminum block integrates the exhaust manifold, while a simplified balance shaft system is intended to improve noise, vibration, and harshness, durability, and overall efficiency. A variable displacement oil pump adjusts oil flow and pressure to suit operating requirements. Cooling performance is supported by an exclusive fully active dual-cooling system designed to keep the engine within its optimal operating temperature. The system is intended to remain effective during extreme operating scenarios, including continuous slope climbing and long-duration operation at high temperatures, where thermal management can become especially demanding.

IPX8 Waterproofing for Deep-Water Wading

Waterproofing is central to the HORSE B20’s off-road positioning. The engine uses a fully sealed waterproof structure with torsional vibration dampers and dedicated engine-transmission sealing to achieve its IPX8 rating. Its electrical components and sensors are also rated for IPX8 protection and continuously monitor the engine’s surrounding operating environment. When the engine becomes submerged, the control system can automatically adjust operation based on sensor feedback, including limiting power or modifying throttle response. These measures are designed to support stable engine operation during deep-water wading. The stated 1.1-meter operating depth gives hybrid vehicle manufacturers a defined capability for applications that require sustained operation in challenging water crossings.

Horse Powertrain on B20 Market Applications

Ingo Scholten, Deputy Chief Technology Officer of Horse Powertrain, said: “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. Supporting HEV, PHEV and REEV platforms, the HORSE B20 enables new opportunities across a range of vehicle categories - particularly off-road applications, due to the engine's waterproofing and climbing capabilities. This engine is another step forward in advancing modern powertrain technology and a further example of how Horse Powertrain is pushing our industry forward.” The statement emphasizes the engine’s intended role as a flexible powertrain solution rather than a unit limited to one hybrid architecture or vehicle category.

Geely Galaxy Cruiser 700 Integration

The HORSE B20 was first showcased at the Beijing Auto Show 2026 and was recently used in a PHEV powertrain in the Geely Galaxy Cruiser 700 off-road vehicle, which is available in China only. In that application, the engine was paired with a HORSE 3DHT230, a 3-speed intelligent hybrid transmission. The vehicle integration provides a concrete example of how the engine can be combined with a plug-in hybrid system for an off-road application. It also demonstrates the intended compatibility between the B20 engine and dedicated hybrid transmission technology, while the China-only application places the current example within the Chinese off-road vehicle market.

Industry Impact & Outlook

The HORSE B20 could broaden the role of combustion engines in hybrid off-road vehicles by combining hybrid compatibility with a defined deep-wading capability and sustained high-load performance. For manufacturers targeting SUVs and pick-up trucks, the engine provides another powertrain option for applications where water protection, climbing performance, thermal management, and fuel efficiency must work together. Its HEV, PHEV, and REEV compatibility may also support different vehicle architectures without requiring a single hybrid configuration. The Geely application in China shows an early vehicle-level use case, while future significance will depend on how manufacturers apply the engine across off-road programs and whether its waterproofing and efficiency characteristics meet the requirements of those markets.

Frequently Asked Questions

What is the HORSE B20 engine designed for?
The HORSE B20 is a 2-liter turbocharged gasoline engine designed for HEV, PHEV, and REEV hybrid applications, particularly SUVs and pick-up trucks intended for demanding off-road use. It can deliver 140-185kW of power and 300-380Nm of torque while achieving 48.4% brake thermal efficiency through its advanced Miller cycle. Its fully sealed structure provides IPX8 waterproofing for operation at depths of up to 1.1 meters, while automatic control adjustments help maintain stable operation during deep-water wading and other extreme operating conditions.