I have driven many many miles online. Never ever have I seen something, that made me suspicious. At some time, there was a debate about speedhacking, in the danish Lfs community. After that somebody saw ghosts (it was only ordinary lag and a very good driver)
That`s the nearest I have been to the subject.
Nobody can cheat, using a sort of speed hack. Most hotlappers, now precisely the max speeds, for a car, on a given place on a track. On Asclub, in some cars, I would be very alarmed if a driver suddenly did 2 km`s faster, down the straigth.
I don`t think it will be possible to cheat many hours, if you race against the "pro`s" of Lfs. They would blow your cover instantly. Those kind of guys can tell from your driving, whether you cheat or not.
It`s nearly impossible, and you will get caugth, if you cheat - So, just don`t do it ! It`s as easy as that