nhra has required a roll bar for anything 11.99 or quicker for years but also I was told if it has a roll bar cage you have to have harness reguardless how fast it is so if your car runs 14.00 and has a roll bar you must have a harness. and if your car is fast a roll bar is a good idea I have 2 friends that have crashed at over 100 miles per hr. both had cages and both are still racing.both went to the hospital for several days but no doubt it saved their lives. ask yourself does your car go 100 on a pass.