[1] The basic engine was originally designed and produced by JLO-Motorenwerke of Germany and was later acquired by the AMW Cuyuna Engine Company of Beaufort, South Carolina and marketed under the Cuyuna brand name.
[1][2][3] The 540 is a conventional twin-cylinder engine that weighs 90 lb (41 kg) in its L70 aircraft version.
The engine features dual capacitor discharge ignition (single in the sport vehicle version), reed valve porting, tuned exhaust system, two slide venturi-type carburetors, liquid cooling, fuel pump, a cast iron cylinder liner, ball, needle and roller bearings throughout.
The aircraft version was offered with an optional gearbox reduction system.
This was done to reduce the displacement to under 500 cc and allow the engine to be used for Formula 500 auto racing.