Main hoop to seat rule ?

On a 8.50 cage nhra rule if I'm reading right were I mount seat back of my helmet needs to be no more than 6 inches from main hoop ?

If so I'm screwed , fairmont is cert 8.50 but must of been for someone 6 ft 4 or something ....main hoop is on hump right behind door I'm 5 ft 8

Pisces me off always something

I think it's a "roll bar" vs "roll cage" deal in the rule book.

IIRC the 6" max helmet to main hoop distance reference only applies to a simple "roll bar" (minimum = main hoop + driver door bar + rear main hoop braces + seat cross bar, but no windshield/halo bars). It doesn't apply to a "roll cage" (as in "full roll cage", that also requires windshield/halo bars). The 6" rule is in effect with a simple roll bar because in a crash the helmet's only protection is the main hoop it's self. But with a full roll cage the 6" rule isn't as important because the helmet is also protected by the windshield/halo bars too.

Helmet protection is also why in "roll cages" it also says "helmet must be in front of main hoop. [but] If helmet is behind or under main hoop, additional tubing same size and thickness as roll cage must be added to protect driver.

DILLIGASDAVE wrote:I think it's a "roll bar" vs "roll cage" deal in the rule book.

IIRC the 6" max helmet to main hoop distance reference only applies to a simple "roll bar" (minimum = main hoop + driver door bar + rear main hoop braces + seat cross bar, but no windshield/halo bars). It doesn't apply to a "roll cage" (as in "full roll cage", that also requires windshield/halo bars). The 6" rule is in effect with a simple roll bar because in a crash the helmet's only protection is the main hoop it's self. But with a full roll cage the 6" rule isn't as important because the helmet is also protected by the windshield/halo bars too.

Helmet protection is also why in "roll cages" it also says "helmet must be in front of main hoop. [but] If helmet is behind or under main hoop, additional tubing same size and thickness as roll cage must be added to protect driver.

thank god ,

i was looking at the main hoop in the fairmont vs my mustang i had a couple of years ago and the hoop looked back a couple inches and i measured ball park were a seat would be if it was 6 inches and there no way my short ass is reaching for any switchs or anything lol

i do not want to move this main hoop , i guess dont go faster than 9.99 and dont worry about it

5pointslow wrote:i do not want to move this main hoop , i guess dont go faster than 9.99 and dont worry about it

Yeah....You'll quit at 9.99.

maverick wrote:

5pointslow wrote:i do not want to move this main hoop , i guess dont go faster than 9.99 and dont worry about it

Yeah....You'll quit at 9.99.  

Lol

Surely at 9.9 you'd want a cage anyhow? IF I'm not missing what others have described, couldn't you at this point just move up to a 10 point cage? I'm in opposite boat and have thought about moving to FC to allow me to move seat back under main hoop.......I'm wadded up in my Mustang as I simply ran out of room when I sat the engine back the 10% / 10.8" into the firewall.