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Discussion Starter #1
I am not sure how many of you are envolved in drag racing your rods, but I thought you guys (and gals) might be able to help me with this one.

I am installing a rollbar in my 74 Gran Torino and according to the NHRA rulebook "All cars with an OEM frame must have roll bar attached to frame".

Is there a way i can attach a rollbar though the body of the car without loosing the effect that the rubber body mounts have on ride quality??

I was thinking of making larger holes in the body and sealing the difference between the hole size and the tube size with some sort of rubber bushing, but thought that this would be the place to ask (someone must have something similar). Or will this effect the ride quality at all???

and sorry for being so long winded
 

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Actually I think you'll find the roll bar installation will improve the handling of your car so much you won't even notice any change in ride quality. Your idea will work as you stated with a seal around the roll bar where it passes through the floorboard. I would suggest that before you do any cutting and welding,go to the track and find some Stock Eliminator cars and ask to see how they did theirs. Most of these guys are pretty cool about stuff like this and will be glad to help.Just don't ask for any go fast secrets. <img src="graemlins/nono.gif" border="0" alt="[nono]" />
 

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That's how to do it except you don't need rubber grommets, silicone sealant works great and seals all the dust out.

Good luck.
 

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Either way listed will work fine. The grommets will be hard to find and require a larger hole. I would use the silicone.

Chris
 

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I have placed roll cages in 2 of my vehicles. Not only did I weld the cage in but of course since they were unibody (Duster and Camaro), I also welded in subframe connectors for them to attach to. While admittedly both cars were on the edge of streetability,I did not notice an appreciable difference in ride quality. The biggest noticeable difference was the way the cars reacted when jacked up in the shop and how they launch at the track. Be very sure that your frame is square and weld the cage in. Your safety and the integrity of the cage far outweighs any ride quality issues you may have. My opinion. Don't forget solid bushings if you weld in.

[ April 03, 2003: Message edited by: FamilyMan ]</p>
 

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Originally posted by FamilyMan:
<strong>I have placed roll cages in 2 of my vehicles. Not only did I weld the cage in but of course since they were unibody (Duster and Camaro), I also welded in subframe connectors for them to attach to. While admittedly both cars were on the edge of streetability,I did not notice an appreciable difference in ride quality. The biggest noticeable difference was the way the cars reacted when jacked up in the shop and how they launch at the track. Be very sure that your frame is square and weld the cage in. Your safety and the integrity of the cage far outweighs any ride quality issues you may have. My opinion. Don't forget solid bushings if you weld in.

[ April 03, 2003: Message edited by: FamilyMan ]</strong><hr></blockquote>

There is no need for solid bushings. It will only make it ride like a tank. It will make the frame a bit more rigid, but is not necissary. Also, On a unibody car, the most solid place to attatch the cage is to the floor area of the car that serves as the frame. That is the area just under the door in most cases. You can then tie the cage to the frame connectors with the main hoop diagonal braces. The body of the car is designed to support the weight of the floor, and is the reason for strengthing that with the cage. The frame connectors do the same thing. Tieing the connectors and floor together via the cage will yield the strongest chassis.

Chris
 

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Good points Turbo, but with the floor, subframe connectors (crossbraced..not the store bought type), floor and cage welded together there was no apparent flexibility gained by using standard bushings and changing them later was quite interesting.

[ April 13, 2003: Message edited by: FamilyMan ]</p>
 

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Originally posted by FamilyMan:
<strong>Good points Turbo, but with the floor, subframe connectors (crossbraced..not the store bought type), floor and cage welded together there was no apparent flexibility gained by using standard bushings and changing them later was quite interesting.

[ April 13, 2003: Message edited by: FamilyMan ]</strong><hr></blockquote>

I guess I am missing what you are saying here. Are you saying that there was no better ride with the rubber bushings? I guess my point was that for a street driven car, the rubber bushings will help isolate the body from drive train noise and vibration. With solid bushings, the car will rattle and rumble worse.

Chris
 

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Discussion Starter #9
i'm trying to get ahold of a tech rep for the nhra and ask if what i am wanting to do is "legal" in thier sence, but no luck as of yet
 

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i also have a question, this is regarding the welding of the roll cage tubing to the vehicle.

i have a chevette that is now a back half tube frame car set up with 4-link. can you weld the roll cage directly to the frame rails? or must you still use the 6" plates?

thx for any info
 

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I have put a couple bars in cars and wanted a clean look and have the floor pan seperate from the bar also. I did it so I can lift the body off the car since it was my first big build up and I figured I would be fixing screw-ups all the time.

The way I did it was to make a 6 inch "stub" that was welded to the frame and put thruoug the floor. I made a slip joint that the main bar came over and bolted together.

To make it clean looking I took a motorcycle innertube and used saftey wire to hold it on. I did not want to see the wire so I put the tube as far up the "stub" As I thought would look good,Saftey wired it on then turned it down (kinda like what your sock does if you just grab the top and pull down) and bolted it to the floor with a shifter boot. Nice clean install and allows for movement between the pan and bar.

Two weeks later I welded the frame/body/cage together in so many places that two Sherman tanks couldnt pull them apart!
 

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grizzly said:
i also have a question, this is regarding the welding of the roll cage tubing to the vehicle.

i have a chevette that is now a back half tube frame car set up with 4-link. can you weld the roll cage directly to the frame rails? or must you still use the 6" plates?

thx for any info
If you ever want to drop the rear frame then I would go with a plate welded to the frame and one to the bottom of the cage and bolt them up. They will be plenty strong and offer you the chance to drop the back half of the car to do stuff to it and removing the bar comes alot easier also. (4) 1/2 inch stainless carriage bolts and nylocks do the trick
 

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Discussion Starter #13
anyone know where i could find poly body mounts?? make it a little more stiff but not as bad as solid mounts
 
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