By Gilles Guillaume TREMERY (Reuters) -World No. 4 carmaker Stellantis said on Wednesday it will speed up electric motor production at its factory in Tremery, France, long the world’s largest diesel engine plant, to account for 50% of the facility’s capacity by 2024. In 2021, diesel accounted for 67% of production at this plant in northeastern France. By 2024, diesel engines will make up only 30% of installed capacity. Gasoline engines, also used for hybrid electric vehicles, will make up 20% of capacity. Via a joint venture with Japanese electric motor maker Nidec, Stellantis plans production…