DD,
Google is your friend....
That said, here's one typical quote:
Quote:
|
the driver's helmet must be below the line from the top of the roll hoop or bar to the top of the windshield
|
This varies a little bit from place to place. Some want one or two inches daylight between the stick and the helmet.
There's also some controversy about this technique because the windshield isn't going to provide any rollover resistance at all - don't ask how I know this.
The real issue is whether the roll bar sticks up high enough to prevent your helmet from touching the ground in case of a rollover. For a Cobra, a couple of inches is probably OK
if the car and bar are stoutly constructed and the bar is not located too far behind the helmet and the belts are properly located, mounted, tightened down and are strong enough.
Hope this helps,
Tom