Engine and vehicle

The invention discloses an engine and a vehicle, the engine comprises an engine body set, the engine body set is provided with an air cylinder, and the cross section area of the air cylinder is S1; the pre-combustion chamber is arranged on the engine body set, the volume of the pre-combustion chamber is V1, and V1 and S1 meet the relational expression that V1/S1 is larger than 0.14 mm and smaller than 0.3 mm. Therefore, the ratio of the volume of the pre-combustion chamber to the cross sectional area of the air cylinder is set in a reasonable range, the volume of the pre-combustion chamber can be reasonably designed according to the cross sectional area of the air cylinder, the proportion of local enriched mixed gas in the pre-combustion chamber can be reduced, oil consumption and original NOx emission can be reduced, ignition energy required by an engine can be met, and the engine efficiency can be improved. Stable ignition and combustion of the engine are guaranteed, and heat efficiency of the engine is imp