Rule book discrepancy: ROLL BAR

Bobby Zlatkin · 09-10-2008, 04:25 AM

If I'm reading the NHRA rule book correctly, there is a discrepancy on pg. #76, 4:10 Roll Bar.

In diagram, 4:10, it states, "All materials must be 1 3/4" O .D. mild steel ................except A, (rear braces that go into the trunk) which is 1 1/4" O.D.

In the paragraph just above the diagram, it states: "Rear braces must be of the same diameter ,,,,,,,,,
as the roll bar.

Which is it? Can I use 1 1/4" for the rear braces or do I have to use 1 3/4"?

Dave Goob Cook · 09-10-2008, 09:10 AM

Wow, I never noticed that, and it does need clarified.
Kits all come with 1 3/4" for all tubes.

Better check with your Division Tech director for a clarification....I'm going to do the same this weekend.

55 Chevy · 09-10-2008, 11:24 AM

That discrepancy has been in the rule book for a long time. I remember noticing that sort of thing and asking about it 15 years ago as it effected me at the time. I think it was all 1 3/4" if I remember right, but not positive.

RPinoski1 · 09-10-2008, 03:22 PM

The cross bar that the seat bolts to is the "A" bar. Not the rear bars. Hope this helps.
Rich

John Mason · 09-10-2008, 05:47 PM

Rich is correct. In older rule books using this picture there was an arrow from the "A" to the cross bar that has been deleted somewhere but the intent remains the same - all parts of the roll bar must be the same size EXCEPT the cross bar.

goinbroke2 · 09-18-2008, 06:02 PM

Here's a question, does the hoop have to be a single piece? What I mean is, I have a bunch of 8ft pieces of 1.75 tube. I am building the roll bar and 8ft is not long enough to go from floor up over and back down to floor. Can I use two pieces of tube and run a joint or splice tube inside? (not a class car but could relate)
I need a piece approx 10 1/2ft long to do it in one piece.

09-10-2008, 04:25 AM	#1
Bobby Zlatkin Member Join Date: Mar 2003 Location: Mills River, NC Posts: 417 Likes: 0 Liked 0 Times in 0 Posts	Rule book discrepancy: ROLL BAR If I'm reading the NHRA rule book correctly, there is a discrepancy on pg. #76, 4:10 Roll Bar. In diagram, 4:10, it states, "All materials must be 1 3/4" O .D. mild steel ................except A, (rear braces that go into the trunk) which is 1 1/4" O.D. In the paragraph just above the diagram, it states: "Rear braces must be of the same diameter ,,,,,,,,, as the roll bar. Which is it? Can I use 1 1/4" for the rear braces or do I have to use 1 3/4"? __________________ Bobby & Norene Zlatkin L/SA

09-10-2008, 09:10 AM	#2
Dave Goob Cook Member Join Date: Dec 2006 Location: Indy Posts: 422 Likes: 0 Liked 0 Times in 0 Posts	Re: Rule book discrepancy: ROLL BAR Wow, I never noticed that, and it does need clarified. Kits all come with 1 3/4" for all tubes. Better check with your Division Tech director for a clarification....I'm going to do the same this weekend.

09-10-2008, 11:24 AM	#3
55 Chevy Member Join Date: Feb 2008 Location: Calgary,Alberta area Posts: 229 Likes: 23 Liked 20 Times in 15 Posts	Re: Rule book discrepancy: ROLL BAR That discrepancy has been in the rule book for a long time. I remember noticing that sort of thing and asking about it 15 years ago as it effected me at the time. I think it was all 1 3/4" if I remember right, but not positive.

09-10-2008, 03:22 PM	#4
RPinoski1 Member Join Date: Jan 2002 Location: PLACERVILLE, CA Posts: 182 Likes: 0 Liked 0 Times in 0 Posts	Re: Rule book discrepancy: ROLL BAR The cross bar that the seat bolts to is the "A" bar. Not the rear bars. Hope this helps. Rich

09-10-2008, 05:47 PM	#5
John Mason Member Join Date: Apr 2002 Posts: 147 Likes: 0 Liked 0 Times in 0 Posts	Re: Rule book discrepancy: ROLL BAR Rich is correct. In older rule books using this picture there was an arrow from the "A" to the cross bar that has been deleted somewhere but the intent remains the same - all parts of the roll bar must be the same size EXCEPT the cross bar. __________________ John Mason 7743 SS

09-18-2008, 06:02 PM	#6
goinbroke2 Senior Member Join Date: Mar 2002 Location: NS CANADA Posts: 899 Likes: 1,682 Liked 403 Times in 158 Posts	Re: Rule book discrepancy: ROLL BAR Here's a question, does the hoop have to be a single piece? What I mean is, I have a bunch of 8ft pieces of 1.75 tube. I am building the roll bar and 8ft is not long enough to go from floor up over and back down to floor. Can I use two pieces of tube and run a joint or splice tube inside? (not a class car but could relate) I need a piece approx 10 1/2ft long to do it in one piece.