Engine Benefits

LiquidPiston’s 4-stroke HEHC-cycle engines are designed to be:

Lightweight and Compact

  • High power density – up to 2 HP/Lb (3.3 kW/kg)
  • 30% smaller and lighter for spark-ignition (SI) gasoline engines
  • Up to 75% smaller and lighter for compression-ignition (CI) diesel engines


  • No poppet valves
  • Exhaust turbulence minimized by over-expansion; no muffler required


  • Only two primary moving parts, optimally balanced, resulting in near-zero vibration


  • 20% decrease in fuel consumption possible for SI gasoline engines
  • 50% decrease in fuel consumption possible for CI diesel engines

Multi-Fuel Capable

  • Diesel, gasoline, natural gas, JP-8


  • From 1 HP to over 1000 HP
How it Works

LiquidPiston’s 70cc X Mini engine (right) next to a
49cc Honda Metropolitan moped engine (left).