Forgive me if this is a stupid question, but is it normal for the revs to blip a slightly whenever you get off and back on the throttle? Is it just the torque converter? The reason I ask is because I've noticed this happening the last couple of weeks since I installed my exhaust and can hear the car now. I spend the majority of my time in traffic and am constantly having to let off of the throttle and get back on it again. Every time I get back on the throttle just enough to maintain speed the revs will rise a few hundred before coming back down.