I grew up near the Rover factory in Solihull. I recall they were experimenting with a gas turbine equipped P5 saloon in the late sixties – local lads used to report spotting it on their test track making the sort of noise you would expect…
Problem with gas turbines is they are slow to spool up so not much use in a conventional car having to wait when the lights change. However as a constant speed device it might happen.