Traction control:on/off/competition

I have a '00 Vette and my traction control only has on and off. I know they made a competition mode on this model also, but don't know how i go about getting that added to my car or how big of a difference it makes. Also, if anyone has any experience with this, do you get better time on the track with the traction control on or off? i know you get more power with it off, but just wondering if you would lose a lot of time on the burn out from the start. guess i need to just time it for myself and see, but would like to know what you guys have to say.