Aftermarket exhaust CAN NOT be illegal. He might be able to get you for noise, but not for type/brand, provided you meet smog/noise specs he's full of ****!. Millions of cars have aftermarket exhausts on them that are not OEM parts. Thread name is right on total BS! Measure the distance from the first stop to the second. Excatly. then fight the ticket in court. ask the Cop how long he paced you. I'm betting he couldn't have paced you for such a short distance, he'd have been accelerating to catch you, not following at the same speed. Judges get pissed at cops who waste their time, and this sounds like a perfect opportunity to go to court and win! Fight it fight it fight it
Mark