The first question is how fast do you want to go? Below are some popular chassis options your door car can be built to

11.49-9.99 – This can be satisfied with just a roll bar. We offer them as an affordable starting point that can be added on to as you go quicker.

9.99-8.50 – Most popular option out there. Commonly know as an “8.50 cage”. Can be built out of mild steel but is weighs more and the cost difference is negligible enough we recommend going chromoly.

7.50 to 8.49 Seconds; 3,600 lbs. Maximum – SFI Spec 25.5E Full Bodied Car Stock or Modified/OEM Floorplan and Firewall with OEM Frame or Uni-Body Construction. This spec can be integrated into your factory floor as shown or can be replaced with a new floor.
7.99 to 8.49 Seconds; 5,000 lbs. Maximum – SFI Spec 25.6A Full Bodied Car Stock / Truck or Modified/OEM Floorpan and Firewall with OEM Frame or Uni-Body Construction
7.50 to 8.49 Seconds; 3,600 lbs. Maximum – SFI Spec 25.4D Full Bodied Car Tube Chassis
6.50 to 7.49 Seconds ET; 3,600 lbs. Maximum – SFI Spec 25.3D Full Bodied Car with Aftermarket Body Shell and Tube Frame, OEM Body Shell and OEM Frame with OEM or Modified Floor pan and Firewall, or Uni-Body with OEM or Modified Floorpan and Firewall Roll Cage
6.00 to 7.49 Seconds ET; 3,200 lbs. Maximum – SFI Spec 25.2E Full Bodied Car Tube Chassis
7.49 Seconds & Quicker; 2,800 lbs. Maximum – SFI Spec 25.1K Full Bodied Car Tube Chassis