The turbo engine is a key component of the new Class 1 regulations, which come into force in the 2019 DTM season. The previous V8 engines are being replaced by efficient and significantly more powerful four-cylinder turbo engines with two-litre capacity. All the modifications required to fit the new engine, in accordance with Class 1 regulations, have already been made on the BMW M4 DTM. These include alterations to the air inlets and outlets, as well as the intake and exhaust system. Further evolutionary phases, based on the new regulations, will be implemented before the new car is homologated.