Euro Truck Simulator 2 (ETS2) , reaching 400 km/h requires bypassing standard engine and transmission physics which typically cap trucks around 160–180 km/h

If you are looking for ways to bypass standard limits on the latest versions, players currently use the following methods: How To Remove 90 km/h Truck Limiter In ETS2/ATS 3 Feb 2022 — How To Remove 90 km/h Truck Limiter In ETS2/ATS Euro Truck Simulator 2 Version history

It seems you’re looking for content related to a , specifically noting that it may be “patched” (no longer working after a game update).