Honestly guys, I can check in FEA but I dont think the door bars are going to help much without the backbone and taking it all the way like I did in my design around the perimeter of the car. Even leaving just a couple tubes out will negate all your work. The time I spent in SW was very enlightening.

James, we can try to work through some senarios with you but the backbone is going to be one of the single best mods you can do to the chassis. You will basically double the chassis stiffness with it.

David