The Saito .56, like most Saito engines, is a 4-stroke glow engine. It runs on the same type of glow fuel as most other RC engines and uses a glow plug rather than a spark ignition system.

Saito does make a couple of larger 4-stroke engines that run on gasoline though. These are spark ignition engines that use an electronic ignition system with a spark plug just similar to mowers, motorcycles and cars.

2-strokes, 4-strokes, glow, gasoline and everything else all have their place. Everything offers some advantages and gives up others.