[purpleRac3r]

My understanding is many groups hosting track events will not allow convertibles without roll bars if speeds are anticipated past a certain point. It has to do with their insurance. If you stick to "driving experience" events, they are more organized like performance driving schools, and tend to be more lenient with convertibles. GM says the convertible windshield frame will hold the weight of the car in the event of a roll-over, but I doubt it would be sufficient at track speeds, especially in a competitive situation. I personally would only track a convertible with a 4-point or better roll bar, just for peace of mind if nothing else. And it would open more track venues up to you.