I put emough bars in it to where if I took a lick in it running over 200 mph I would feel safe. I know it will pass with less, but it just makes me feel better sitting in it I guess is the best answer. I put an x between inner and outer framerails on both sides of the floor, in the tunnel, and a few extra bars tieing it all to the stock front and rear frame rails. What spec are you looking at doing? A,B, or C.