Technical specifications
| Manufacturer | Officine Meccaniche Colombo, Milan, Italy, from 1928 to 1930s |
| Type | S. 53 |
| Description | aircraft engine with 4-inline cylinders, aluminium crankcase with 5 main bearings, steel-made cylinders, headd and pistons in aluminium alloy |
| Stroke | 140 mm |
| Bore | 114 mm |
| Displacement | 5710 cm³ |
| Compression ratio | 5.24 |
| Power | 94 hp at 1900 rpm at sea level |
| Specific fuel consumption | 230 g/hp/h |
| Specific power | 16.5 hp/litre |
| Valvetrain system | 2 overhead valves per cylinder, operated by pushrods and rocker arms controlled by a gear-driven camshaft housed in the crankcase |
| Fuel feeding system | with one single-barrel gasoline carburetor Zenith 48 J 9, with an inlet mixture heater |
| Ignition system | with two Marelli H4 spark plugs per cylinder fed by two Marelli SA4 magneto distributors |
| Cooling system | air-fed |
| Lubrication system | forced by a feeding gear pump and one scavenge gear pump |
| Weight | 105 kg |
| Mass-to-power ratio | 1.1 kg/hp |
