smart at 200 on my bumper

Hello together I picked up my new wheels for my smart yesterday(Brabus 195 round around) for this reason I drove with my electric class there so on the track easy with 160,until suddenly a wise 451 was behind me and blinked!! so I was on the gas up to 200 there was the guy still behind me! so what the devil was that? he was extremely deep and wide and so fast,I had to speed up to 220 so I got away from him my brother has a brabus the läut 170, so there must have been more done? Greetings frank