NHRA Roll Bar Regs?

[PhilC]

With regard to the roll bar that is required when running 1/4 mile times under 11.99 and would be good until you reach the 9.99 barrier, is there a hoop that simply goes behind the two seats and does not go down along the side by the door which would be in compliance? The car is a street car and always will be and I hate the thought of having to climb out over the bar.

Thanks, Phil

 

[Tom Welch]

Phil,

The NHRA minimum requirements for roll bars installed in FULL BODIED cars with the factory floor and firewall that have elapsed times from 11.99 to 10.00 are as follows:

1. Must be constructed of .118" minimum wall thickness steel tube.

2. Must have 5 attaching points to either the vehicle frame or floorpan or a combination of both.(the NHRA rule book gives guidelines for approximate locations of attaching point positions with regards to full bodied cars)one of which must be a sidebar on the drivers side.

3. Must have a sidebar on the drivers side that when installed intersects a line between the drivers shoulder and elbow while driver is in the seated position. This sidebar may be removable but must be in place during track events.

4. Roll bar may mount to the vehicle by any of these three methods. Bolt to existing frame members, bolt through the floorpan with "sandwiching plates", weld to the vehicle frame.

With those basic guidelines in mind we constructed a Viper Roll bar and you can see pictures of it on my website at the link below. Our Roll Bars are constructed of .120" wall steel. The sidebar is removealbe, the bar installs with no welding or cutting on your frame. The bar is 100% removeable should you ever decide to eliminate it. Our Roll bars come with 2 sets of 5 way harnesses(Teamtech-RJS).

Thanks for your question.

Tom
Http://btrviper.com

 

[MES]

I installed the BTR rollbar several weeks ago. It fit perfectly. I don't know how BTR gets all the bends and holes to line up but if any were 1/4" off it would not have fit. The drivers seat don't go completely back due to the bar, it sits one click forward from the completely back position. Other than that I can't tell it's in the car.

I think BTR and Autoform are the only two companies that make pre-welded setups for roll bars. I chose BTR because it had the least obstructions looking out the rear view mirror. Unless Autoform changed their design the pictures show cross braces that form a "M" which seems to make it very hard to see out the rear view mirror on the street. If I'm wrong someone with the Autoform bar correct me.

With either bar you do loose the stock seat belts. The upper mounting points for the bars go where the stock retractors mount. So your forced to wear the 5 way harness all the time (4 way really because you don't need the one between the seat). See if Tom can upgrade you to the clamlock harness rather than the latch and link type, it's more comfortable/practical for street use. Except for spending 20 seconds poking the seatbelt ends out of the way when I exit the car so when I get back in they don't stab me in the rear and back, the car is just as drivable/comfortable as a stock car.

I have some pictures on my web site below.

 

[pauls]

If you have an IHRA track you aren't required to have a bar until 11.50. I've convinced the tech guys at several NHRA tracks that the hoop in a stock coupe is good enough for a roll bar. All depends on your salesmanship. Norwalk Oh, home of the Viper Nationals, lets coupes run to 11.00 without a bar. Now, no one has ever asked me if the car has a blowproof bellhousing.

 

[Greg D]

All materials MUST be 1 3/4" OD x .118" mild steel OR .083" chrome moly except the back brace bar which is 1 1/4" OD x .118 mild steel or .083 chrome moly.

All roll bars MUST be within 6 inches of the rear or side of the driver's head, extend in height at least 3 inches above the driver's helmet with driver in normal driving position and be at least as wide as the driver's shoulder or within 1 inch of the drver's door.

Roll bar must be adequately supported or cross-braced to prevent forward or lateral collaspe.

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 to of the roll bar.

All roll bars MUST have in their construction a cross bar for seat bracing and as the shoulder harness attachment point. Cross bar MUST be installed no more than 4 inches below and not above, the driver's shouldes or to the sidebar.

Any car where a roll bar is installed, a padded head protector
must be provided a the back of the driver's head an constructedin an attempt to prevent whiplash upon impact. The roll bar MUST be padded wherever it may come in contact with the driver's helmet. Adequate padding should permit approx 1/4" of compression OR meet SFI spec 45.1. The use of weather stripping or similar thin/low impact resisting materials is prohibited.

As a suggestion, buy one harness (since they are dated and MUST be replaced every two years) and when the first harness becomes outdated, buy second of the same model, install it on the driver's side and transfer the outdated harness to the passenger's side since.

 

[PhilC]

Thanks everyone for your responses. A couple of problems come to the surface though. Tom, is there a way around the fact that the seat can no longer go all the way back. I'm 6'5" and it's important for the seat to go all the way back or my knees will hit the dash. I've installed the seat lowering kit (1" variety) and I now fit comfortably with the helmet on but one of the posts indicated that the bar had to be at least three inches above drivers helmet (there are 0 inches above my helmet to spare) Thanks again,

Phil

 

[Tom Welch]

Phil,

I recently installed a bar in a 2001 GTS whos owner is a large fellow. He also had the seat lowering kit. His seat has full travel. Im not sure what happened with Mikes install. Myself, Im only 5' 8" and i don't recline my seat very much when seated, although it is all the way back. My seat has full travel, but I do not recline the seat back as much as other folks might. That may be the restriction with Mikes.

If you want to speak with the customer with the seat lowered and the bar installed, email me and I will forward his number.

Also, we have installed bars in all model years of GTS vipers and have found that the final fit is clean and OEM in its appearance even though the cars all seem to have minor tolerance differences..........I can only assume its because they are hand built. We have seen this same pheonomonon with regards to exhaust system installs and other items.

Thanks again, and good luck with your search.

Tom Http://btrviper.com

BTW, Mike,

Thanks for the plug! How's that NOS install coming?

Greg,

Your section about the cross brace for seat bracing and seatbelt mounting is not needed in factory floor/seat/firewall vehicles. Especially 2 passenger vehicles with the frame behined the seats like the Viper.

Pauls,

Nice point! Its amazing how a tech inspector will look at your car, not see the roll bar--and slap the book at you. I have been kicked out for not having a roll bar one night then allowed to race at that same track the next week!????. I got tired of the gymnastics involved with talking my way through these things and designed the bar that I use and sell. There are other items that can disqualify the Viper from NHRA tech, one of which you mentioned. Run 10.99 and faster and a whole new group of items needs to be addressed, most of which never get teched....like aftermarket wheelstuds.