Cage install in Progress
Staging Lane
Joined: Apr 2005
Posts: 92
Likes: 0
From: Westminster, MD
ced directly out of the NHRA rulebook page 79, General Regulations, Section 4.
"Unless an OEM framerail is located below and outside of driver's legs (i.e. '55 Chevy, '65 Corvette, etc) a rocker or sill bar, minimum 1 5/8 inch x .083 CM or .118 MS or 2 inch x 2 inch x .058 inch CM or MS rectangular, is mandatory in any car with a modified floor or rocker box within the roll cage uprights (excluding 6 square feet of transmission maintence opening). Rocker bar must be installed below and outside of driver's legs andmust tie into the main hoop, the forward hoop, frame, frame extension, or side diagonal. Rocker bar may not tie into swing out side bar support. If rocker bar ties into side diagonal more than 5" (edge to edge) from forward cage support of main hoop, a 1 5/8 inch x .083 CM or .118 MS brace/gusset is mandatory between the diagonal and the forward roll cage support or main hoop."
Now the confusion comes in as to whether or not in a uni-body car the rocker bar constitutes a frame rail outside the drivers leg. IMO the rocker box does not constitute as a frame rail as the frame rail both front and read end under the car some distance inside from the rockers. When installing frame connectors they are under the driver, not outside the driver.
For safety and legality sake, it would be wise to add the rocker bars.
For example, full frame cars like my Malibu or older Chevelles the frame is outside of the driver and the rocker/sill bar is not required.
"Unless an OEM framerail is located below and outside of driver's legs (i.e. '55 Chevy, '65 Corvette, etc) a rocker or sill bar, minimum 1 5/8 inch x .083 CM or .118 MS or 2 inch x 2 inch x .058 inch CM or MS rectangular, is mandatory in any car with a modified floor or rocker box within the roll cage uprights (excluding 6 square feet of transmission maintence opening). Rocker bar must be installed below and outside of driver's legs andmust tie into the main hoop, the forward hoop, frame, frame extension, or side diagonal. Rocker bar may not tie into swing out side bar support. If rocker bar ties into side diagonal more than 5" (edge to edge) from forward cage support of main hoop, a 1 5/8 inch x .083 CM or .118 MS brace/gusset is mandatory between the diagonal and the forward roll cage support or main hoop."
Now the confusion comes in as to whether or not in a uni-body car the rocker bar constitutes a frame rail outside the drivers leg. IMO the rocker box does not constitute as a frame rail as the frame rail both front and read end under the car some distance inside from the rockers. When installing frame connectors they are under the driver, not outside the driver.
For safety and legality sake, it would be wise to add the rocker bars.
For example, full frame cars like my Malibu or older Chevelles the frame is outside of the driver and the rocker/sill bar is not required.
I have a NHRA 8.50 sticker on my cage, the Southeast NHRA tech director did it himself. I asked about the rocker bar before before he put the sticker on and he said its only needed if the floor was modified.
"is mandatory in any car with a modified floor or rocker box within the roll cage uprights" Stock floor/rockers = not required. If the floor has been modified and it has outer frame rails then its not needed either.
For safety you can put a lot more bars in that arent required but its not needed to be legal.
"is mandatory in any car with a modified floor or rocker box within the roll cage uprights" Stock floor/rockers = not required. If the floor has been modified and it has outer frame rails then its not needed either.
For safety you can put a lot more bars in that arent required but its not needed to be legal.
7 Second Club
iTrader: (5)
Joined: Nov 2001
Posts: 8,834
Likes: 1
From: Gainesville, Florida # of drag strips runs: ?!?!?
I was told by the NHRA division 2 tech director as well as the shop that did my bar/cage that a car with swing-outs requires an additional rocker bar on the driver's side since that is replacing the what would be otherwise solidly mounted door bar. Now this was done in 2007, so the rules may have changed since then, but that's how not only my car but quite a few stock firewall, frame and floorpan cars are done.
But I could be mistaken.
Derek
But I could be mistaken.
Derek
The more you're around this stuff, the more you'll see that there are huge discrepancies on what is legal depending on who is doing the inspection.
One more tidbit; you're highly unlikely to win an argument with your inspector.
One more tidbit; you're highly unlikely to win an argument with your inspector.
__________________
1966 Chevy II twin turbo LS3 project
2016 Z07 Carbon
1966 Chevy II twin turbo LS3 project
2016 Z07 Carbon
Joined: Nov 2001
Posts: 8,484
Likes: 0
From: Cecil County Raceway!!!
But the 8.50 cages are very well explained in the rulebook and not much room for interpretation there.
Joined: Nov 2001
Posts: 10,023
Likes: 6
From: LT1 land...the "409" of the 90s!
I think one thing many should read in ANY rule book is. . . All rules are to the inturpitation of the inspector. I am sure more then one person here has been nailed for some thing they were slidding on at one time or another.
If you only ever race at one track you are good to go. If you plan on travling cover all your bases
Nice cage Ryan!
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