Roll bars, rules and the envelop

[Clay Thompson]

I've searched and read most every post and looked at every image of roll bar installations on the board. I want a safe, non-intrusive roll bar that will still allow someone to get into the back seat.

As I understand the rules, there has to be a lower cross bar and it has to be welded in but removable side bars are OK--right?

How about I put my side bars in place and weld the cross bar to the side bars close to the loop. That way, I could pop out the side bars and the lower cross bar would come with it which would leave me with a four point roll bar and easy access to the back seat.

You think an NHRA inspector would OK such and arrangement? Technically, it meets the "letter of the law."

 

[azgn]

maybe you should look at the NHRA rule book....they have real good pictures of what is required.....don't waste your $$ on something that won't pass and isn't safe.....or

slow down

 

[J Banning]

Question #1: Yes.

Question #2: Nope.

And as Woody said, take a look at the current NHRA rule book (just came out) for 100% correct info on what you need to do in regards to that roll bar.

-Banning.

 

[Doug Jacobson]

As is stated in section 4:10 of the 2002 rule book

"All roll bars must be within 6 inches of the rear, or side of the drivers head, extend in height at least 3 inches above the drivers helmet witht he driver in the normal driving position, and be at least as wide as the drivers shoulders or within 1 inch of the drivers door. Roll bar must be adequatetely supported or cross-braced to prevent forward or laterial colapse. Rear braces must be of the same diameter and wall thickness as the roll bar and intersect with the roll bar at a point not more than 5 inches from the top of the roll bar. Sidebar must be included on the drivers sideand must pass the driver at a point midway between the shoulder and elbow. Swing out sidebar permitted. All roll bars must have in their construction a cross bar for seat bracing andas the shoulder harness attachment point; cross bar must be installedno more than 4 inches below, and not above the drivers shoulders or to side bar. All vehicles with OEm frame must have the roll bar welded or bolted to the frame; installation of frame connectors on unibody cars does not constitute a frame, therefor it is not necessary to have the roll bar attached tot he frame. Unibody cars with stock floor and firewall (wheeltubs permitted) may attach the roll bar with 6-inch x 6-inch x .125-inch steel plates on top and bottom of floor bolted together with at least four 3/8-inch bolts, or weld main hoop to rocker sill area with .125-inch reinforcing plates, with plates welded completly. All 4130 chromoly tube welding must be done by approved TIG heliarc process; mild steel welding must be done by approved MIG wire feed or TIG heliarc process. Welding must be free of of slag and porosity. Any grinding of welds prohibited. See illistration> Roll bar must be padded anywhere drivers helmet may contact it while in driving postition. Adequate padding must have minimum 1/4-inch compresion or meet SFI Spec 45.1"

 

[Mark E.]

I put swingouts on the seat bar. Easy access to back seat. At the track, I bolt both sides and slide foam over. I do not think they would bother you on a 11 second car, but you never know. How fast are you planning on going. Good Luck,

 

[J Banning]

Doug: Thanks for posting that info. Did you copy that info from somewhere on the NHRA Web site, or did you write it word for word from the rulebook?

Thanks.

 

[Whistlin'87GN]

Hey Guys, sorry for changing the subject but what is the speed at which a roll bar is required? Also, where is the NHRA rule book available or is there a place where it can be read online?
It will be a while before im as fast as any of you guys are, but Im gonna start dreaming!
-Jeff

 

[Gbodynutt]

Whistlin, a rollbar is required on cars running 11.99 sec. and faster at NHRA tracks. You can buy the rule book from places like Summit or your local speed shop should have some also. You can also get one free if you register with NHRA. Or I believe it's on NHRA's web site also.

 

[Doug Jacobson]

Banning, I downloaded a PDF file a while ago, gave the computer to my parents and now I'm home for the holidays so I used some of the info. Sorry the link is dead to the place I got it from now though. I'm going to send it back to myself though so give me an e-mail if you want it.

Doug J

 

[Turbojorge]

As Gbodynut stated, you need one as soon as you go faster than 11.99, along with a 5 point harness and a drive shaft safety loop. At least that was the lecture I got at the track when I got kicked out. I told him O.K., I'll have at least one of those three for next time .

Kind of sucks when you only run 11.97 and you get kicked out for no roll bar though. Actually, the guys at the track is always confusing me with 3 other guys (blackshoebox being one). Idiots. They almost kicked me out before I even did my first burn out last time I went.

 

[Kansas T]

Originally posted by Doug Jacobson
As is stated in section 4:10 of the 2002 rule book

All vehicles with OEm frame must have the roll bar welded or bolted to the frame

So the roll bar can be bolted to the frame? I've always heard it was required to weld them in.

 

[Whistlin'87GN]

Thanks guys for the info! I'll have to start looking around for a rule book!
-Jeff

 

[John Larkin]

http://208.2.76.252/NHRA rules.htm

Try that out.

 

[turbodave231]

IHRA rules state 11.49 and faster. I don't know about their construction rules....but I don't think a bolt in crossbar will fly with a strict inspector. Most of the tracks I go to barely look at anybody's car unless it looks like a piece of sh-t.

DR

 

[Clay Thompson]

Confusion between roll bar and cage?

I read the rule from John Larkin's link. If that is the current rule, then there seems to be some confusion between the rules governing a roll bar and a roll cage. The way I read the rule for Roll Bars, no cross brace is required.

4.10 ROLL BARS

All roll bars must be within 6-inches (15.2 cm) of the rear, or side, of the driver's head, extend in height at least 3-inches (7.6 cm) above the driver's helmet with driver in normal driving position, and be at least as wide as the driver's shoulders or within 1-inch (2.5 cm) of the driver's door. Roll bar must be adequately supported or cross-braced to prevent forward or lateral collapse of roll bar. Rear braces must be of the same diameter and wall thickness as the roll bar and intersect with the roll bar at a point not more than 5-inches (12.7 cm) from the top of the roll bar. Sidebar must be included on driver's side. The side bar must pass the driver at a point midway between the shoulder and elbow. All vehicles with OEM frame must have roll bar attached to frame; installation of frame connectors on unibody cars does not constitute a frame and therefore it is not necessary to have the roll bar attached to the frame. Unibody cars with stock floor and firewall (wheel tubs permitted) may attach roll bar with 6-inch (15.2 cm) x 6-inch (15.2 cm) x .125-inch (3.2 mm) steel plates on top and bottom of floor bolted together with at least four 3/8-inch (9.53 mm) bolts and nuts, or weld main hoop to rocker sill area with .125-inch (3.2 mm) reinforcing plates. All 4130 chrome moly welding must be done by approved TIG Heliarc process; mild steel (or ST51) welding must be approved MIG wire feed or approved TIG heliarc process. Welding must be free of slag and porosity. Any grinding of welds prohibited. See illustration (Drawing 12).

Roll bar must be padded anywhere driver's helmet may contact it while in driving position. Adequate padding must have minimum 1/4-inch (6.35 mm) compression or meet SFI Spec 45.1.

 

[Chuck Leeper]

NHRA SEZ!

Read it and weep!

Per E. Lowe at NHRA:

The swing out sidebar is legal in roll bars (it states this on pg 209,4:10, 5th sentence) as long as they follow the same standards found under the swing out bars section under the roll cage (with the exception that it must be 1 3/4" dia). As for the connections, they must be done as listed in the swing out bar section. The bottom connection cannot be done with a sliding sleeve (states this in section D). They must use the described arrangement in section B. You are correct in the reason for not being able to use the bottom sleeve. As for the crossbar, the only bolt-in (removable) bars that we allow are the swing-out side bars. The cross bar must be welded in. The only exception to this is if the car does not require a roll bar or cage and therefore, the bars can be done whatever way they want, but as soon as they run fast enough to require a bar, it will need to be changed. If you have more questions, please feel free to contact us.

NHRA Tech Dept.

The old saying goes: If you have a $5.00 head, buy a $5.00 helmet.. Guess the same applies to a roll bar...

Jorge said:
Kind of sucks when you only run 11.97 and you get kicked out for no roll bar though. Actually, the guys at the track is always confusing me with 3 other guys (blackshoebox being one). Idiots. They almost kicked me out before I even did my first burn out last time I went.

That "Only 11.97" is kinda like being pregnant.. Either you are or you aren't.. Either you go quicker than 11.99 or you don't!!

In the FWIW dept.. For those that don't have a bar, the difference in the way the car handles and launches is the difference between day and nite!! It's WELL worth doing it right!!

HAPPY HOLIDAYS!!

 

[J Banning]

Thanks for posting the links guys. To be safe though, get a official NHRA rulebook... you never know how old some of the info is that you're getting off of the Net.

-Banning.

 

[NastyGn]

Originally posted by Kansas T
So the roll bar can be bolted to the frame? I've always heard it was required to weld them in.

What you heard is correct. The rules state if you have a frame the bar must be welded in.

This discussion has come up before and because our cars have a clam shell frame people think they can bolt it in. The key word is frame and yes we have a frame.

As has been posted, if your going to play in this area of speed get the rule book or call NHRA's tech line in your area. Also it don't hurt to check with the tech at you local track either, some of these people get a different meaning out of the rules sometimes.

Take Care