LiquidPiston creates revolutionary ultra-compact rotary engine

LiquidPiston, a start-up company based in the US state of Connecticut, has installed a 70cc prototype X mini engine into a go-kart.

LiquidPiston X engine

The revolutionary new engine, which weighs just 18kg and puts out 5kW, offers a power density of 3.3kW/kg. In addition, it is 30 per cent smaller than a conventional, comparable four-stroke piston engine.

The design itself has more in common with a Wankel rotary than the Otto cycle four-stroke most vehicles use today. Called the X engine, it uses a completely different type of combustion cycle known as the High Energy Hybrid Cycle. It is fuel-agnostic, meaning many different fuels are suitable, and a compression ignition version exists for diesel applications.

LiquidPiston X comparison

It has three spark plugs, so combustion occurs three times during a cycle. This is a major benefit of the design, as are its incredibly low weight and lack of moving parts. It is also said to be simple to manufacture. Check out the video below for more.

Dynamic Display Ad(Long Version)

Primarily, the company is focussed on small motor applications such as generators, garden accessories, but also boats and mopeds. The company mentions suitability for motor vehicles, but mainly as a range extender for hybrid powerplants – much in the same way BMW provides a range-extender engine option for its i3.

Mitchell is a contributing journalist at PerformanceDrive. He has been a passionate petrol-head from a very young age. He is excited by the future of the industry, and considers himself as a bit of a fanatic when it comes to the technical aspects of cars. He is also fascinated by new cars that are popping up in developing markets.