Question on Cages

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Drg racr

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I had a buddy looking over my 'cuda and he seems to think my car won't pass tech with the current roll bar setup it has. I'll admit the roll bar is probably 20 years old, since that's how long it's been sitting in the barn. How much change has there been in 20 years? Anyone know the current IHRA specs on cage/roll bar installation? I have no way of measuring tube wall thickness.
The reason he said that is the fact that my 1/8" floor plates are not flat on the floor due to the curves in the floor. It looks like they welded small risers ( like a box shape) in the uneven areas to make it level. Also, on the trunk bars, they trimmed the floor plates for the spare tire well area. Last I knew the plates had to be 6" square min, 1/8" thick.
 
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I used to have a small paperback book with NHRA IHRA specs, not sure where we obtained it anymore or where it is currently but a Google search will probably yeild good results, I don't remember any specifics about the floor plates but more so location of the hoop bar in reference to the driver seat, and the door bar height, think I had to be within 6 inches behind the seat for the hoop. Around here they don't check the cert unless you are close to the 9s, our car ran 10.40 all day long and they never asked for the cert or looked for the sticker, they were more worried about me having a drives shaft loop, rollover valve for the fuel cell and a battery shutoff switch, I had an old open faced helmet for Pete sake. I had plates welded to the floor sheetmetal and they were trimmed less than 6 inches and the inner hoop bars that run at an angle toward the floor behind the seat were through the floor and welded directly to the frame connector. I would just take it to the track and the worst they can say is no. ???
 
First how fast is this car thats been sitting in a barn for 20 years going to be ?
 
Regarding floor plates: 6"by 6" plates MUST be securely welded to the floor, top and bottom if it is not welded to the frame. I believe that if the plates are securely welded to the spacers and the spacers are securely welded to the floor you are good. It is always best to ask the tech director at the track. If it won't pass I'm thinking it is an easy fix. Good luck
 
I was hoping to build a 10-second bracket car with it, but maybe I'll lower my expectations and try for 11.90's. Next time I go to Muncie Dragway I'll pick up a rule book.
 
This is exactly why I was asking how fast the car was expecting to go, directly concerning your concerns about your roll bar. It won't need one Unless it's going 11.5 or less. And it won't need to be certified unless you're doing under 10 seconds.
I was hoping to build a 10-second bracket car with it, but maybe I'll lower my expectations and try for 11.90's. Next time I go to Muncie Dragway I'll pick up a rule book.
 
Well, with us gearheads, it's never fast enough. I know I'll keep tweaking and throwing money at it until it reaches the point that a cage is needed.
 
The plates do not need to be 6x6 but they do need to be the same amount of square inches as a 6x6 plate, for instance a 4x9 plate would be acceptable. You can bend the plates to match the floor shape, not sure about the boxes you describe without seeing a pic.
 
The plates do not need to be 6x6 but they do need to be the same amount of square inches as a 6x6 plate, for instance a 4x9 plate would be acceptable. You can bend the plates to match the floor shape, not sure about the boxes you describe without seeing a pic.
Seeing a picture would help truemendously...
 
Roll BARS do not need to be certified...only Roll CAGES where the car run faster than 9.99 and/or 135 mph....for NHRA rule book...
 
Unibody cars with stock floor and firewall (wheeltubs


permitted) may attach 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 and nuts, or weld main hoop to rocker sill

area with .125-inch reinforcing plates, with plates welded

completely. Also, the roll bar may be welded to frame connectors

that are fully welded in place and are 1 5/8 inches x .118-inch

MS or .083-inch CM round and/or 2 inch x 2 inch x .058 MS or

CM rectangular.
 
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. Crossbar and rear braces must be welded

to main hoop. Sidebar must be included on driver’s side and 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 and as the

shoulder harness attachment point; cross bar must be installed

no more than 4 inches below, and not above, the driver’s

shoulders or to side bar. All vehicles with OEM frame must have

roll bar welded or bolted to frame; installation of frame

connectors on unibody cars does not constitute a frame;

therefore it is not necessary to have the roll bar attached to the

frame.
 
Trunk Bar.JPG
 
.... NHRA IHRA specs,............a Google search will probably yeild good result..........

^^ If you search there are places you can download the rules, or at least read them online. I'd go find one for you, but these tend to change over time.
 
Tube doesn't appear to be the correct thickness, I don't think that "box" would pass as it's not really even a box, the plates are not full welded, that tube on the plate isn't fully welded or even fully in contact with the plate, you can tell none of the joints were fitted properly and then they just filled them with horrible welds.

I know that's hard to hear and I'm not trying to be a jerk, just telling you all the issues I see.
 
Yup, that's all gotta go...

A cage made like that is more dangerous than no cage. If/when you crash all that tube will become spears inside the car and guess where you will be sitting....

Cut it out and start over.
 
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