A Motorola radio is not fast in and of itself. Actually, I'm not sure it even has the power to move itself. So, in some respects, even Kelu's car is faster than a Motorola radio.
Plus, no cops even know what kind of car the solstice is. One time I was being chased I heard the cop say on the radio he was chasing a late model blue Porsche. Another time, a cop said he was chasing a karman ghia with a body kit. I got away both times.