What is Firing Order - Firing Order For 3, 4, 5, 6, 7, 8 Reasons for preferring 1-3-4-2 than the 1-2-3-4 in 4 cylinder engine: 1. The power impulses are evenly distributed and are 180 degrees apart. Therefore the firing order for the engine is 1-3-4-2. This balance load on two bearings would be further reducing the engine vibrations. Turning Moment Diagram – Single, Four Cylinder, 4-8-2 - Wikipedia Altogether 275 4-8-2 locomotives were built for French service. The Chemins de fer de l'Est (Est) took delivery of a prototype 4-8-2 four-cylinder compound locomotive from its own Épernay shops in 1925. This was the first Mountain type to be built for commercial service within France. Reciprocating engine - Wikipedia These operations are repeated cyclically and an engine is said to be 2-stroke, 4-stroke or 6-stroke depending on the number of strokes it takes to complete a cycle. In some steam engines, the cylinders may be of varying size with the smallest bore cylinder working the highest pressure steam.