I think Jeepspeed follows SCORE(score class 3 with the jeepspeed rule modifications, I think).Vehicle Weight
Under 2000 lbs. 1.5" x 0.95"
2001 to 2500 lbs. 1.5" x .120"
2501 to 3000 lbs. 1.75" x .095"
3001 to 4000 lbs 1.75" x .120"
4001 pounds and over 2.0” x .120”
Here's where you can download the Jeepspeed rules.2.0 Sanctioning Body Regulations: JeepSpeed rules do not in any way replace or modify the competition and safety regulations issued by the race organizer or sanctioning body. Stock or Production class rules will apply in Jeepspeed Challenge Class 1700 (or SCORE Class 3 rules in Jeepspeed Cup Class 3700 ) unless modifications are specifically allowed herein.
Go 2" .120 wall. If I remember right, a race XJ can tip 4000 lbs when race prepped (cage, seats, fuel cell, etc). I may be wrong though.....
You probably shouldn't plan on racing MDR too soon.no BITD or SCORE. MDR