The removable bar will fail tech inspection most likely. Again, consult the pros at the shop I mentioned. Your safety is of paramount concern to a few more dollars.

Also it was Dale Earnhardt who died, when his car went into the #4 turn wall at Daytona. He hit the wall nearly perpendicular, after losing traction running down low in turn 3. He collided with the CMU track wall at well over 120 mph; he died of cerebral hemmorage resulting from a lack of proper restraint at the head. The HANS (Head And Neck Support) device is now mandatory as a result of Earnhardt's crash - it was reccomended before.

My point is to recreate the same conditions in 1/4 mile racing, you'll be forced to wear a helmet and install a full cage before the techs at Infineon / Sears Point ever let you run.

Don't skimp on safety. Please.