Rollbars - weld-in or bolt in? Recommendations?
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Rollbars - weld-in or bolt in? Recommendations?
I've been looking at Safety Devices bolt-in rollbar. It seems to be the only homologated option available. There are a bunch of others available, but they look primarily cosmetic. Does anyone know which bar Rod Emory uses? It looks like GT Werks. Are there advantages to weld-in bars over bolt-ins?
- Glen Hamner, Jr
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Re: Rollbars - weld-in or bolt in? Recommendations?
Hi David,
Regardless of your selection, consider the chassis metal to which the bar is being attached. Then consider the bars ability to transfer any loads to that supporting structure.
Chassis metal in general is light and receives its strength through the integrated rigidity of the folding metal linking all its metal plates to one another. Regardless of your installation choice, the utility of the roll bar will only be as good as its integration with the chassis metal, which you know is light gauge.
For the roll bar to reasonably distribute its loads to the chassis, there needs to be enough metal in contact with the bars mounting plates to transfer the loads across a large expanse of the chassis metal. Large area backing (reinforcement) plates should be installed in the mounting areas to insure the bars loads are carried to the chassis, and not transferred through the chassis wall, i.e., tearing through the light chassis wall at the point of attachment.
In my opinion, both mounting methods are only reasonable if the chassis areas for attachment are properly reinforced to accept the anticipated loads of a high speed roll over or hitting the immovable wall, top first.
Regardless of your selection, consider the chassis metal to which the bar is being attached. Then consider the bars ability to transfer any loads to that supporting structure.
Chassis metal in general is light and receives its strength through the integrated rigidity of the folding metal linking all its metal plates to one another. Regardless of your installation choice, the utility of the roll bar will only be as good as its integration with the chassis metal, which you know is light gauge.
For the roll bar to reasonably distribute its loads to the chassis, there needs to be enough metal in contact with the bars mounting plates to transfer the loads across a large expanse of the chassis metal. Large area backing (reinforcement) plates should be installed in the mounting areas to insure the bars loads are carried to the chassis, and not transferred through the chassis wall, i.e., tearing through the light chassis wall at the point of attachment.
In my opinion, both mounting methods are only reasonable if the chassis areas for attachment are properly reinforced to accept the anticipated loads of a high speed roll over or hitting the immovable wall, top first.
- Craig Richter
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Re: Rollbars - weld-in or bolt in? Recommendations?
David,
I've seen the results of several roll-overs. In fact, I was in one of them. My advice is to forget about roll bars in street cars. All they will do is hurt you.
I've seen the results of several roll-overs. In fact, I was in one of them. My advice is to forget about roll bars in street cars. All they will do is hurt you.
- C J Murray
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Re: Rollbars - weld-in or bolt in? Recommendations?
Craig is right. In racing we wear a helmet and wrap the bar with a special high density material to avoid head injury. No helmet and no ugly padding and you are in great danger. Unfortunately I speak from experience...
'57 Speedster
'59 Sunroof
'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion
'59 Sunroof
'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion
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Re: Rollbars - weld-in or bolt in? Recommendations?
It's important to note that this was not a planned experiment by Cliff trying to test the integrity of his bar!
Edited to rephrase the comment for clarification
Edited to rephrase the comment for clarification
< Jeff >
Registry Member Since 1978
1963 356B T-6 Super 90 Coupe
2009 997.2 Carrera S
2015 958 Cayenne diesel-1 & 2015 958 Cayenne diesel-2
Registry Member Since 1978
1963 356B T-6 Super 90 Coupe
2009 997.2 Carrera S
2015 958 Cayenne diesel-1 & 2015 958 Cayenne diesel-2
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Re: Rollbars - weld-in or bolt in? Recommendations?
I agree...no roll cages for street. But, how about a 2 or 4 point roll bar...i.e., all bars behind the front seat and out of range of your unprotected head. This would offer little stiffening of the chassis but would offer roll over protection. Just a thought.
Conrad
Conrad
- Emil Wojcik
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Re: Rollbars - weld-in or bolt in? Recommendations?
Glen's and Cliff's comments still apply. It's more likely that the bar will just be torn from the mounting points, potentially causing even greater harm than if it didn't have a roll bar. If it breaks free it could still contact your head.Conrad Carter wrote:I agree...no roll cages for street. But, how about a 2 or 4 point roll bar...i.e., all bars behind the front seat and out of range of your unprotected head. This would offer little stiffening of the chassis but would offer roll over protection. Just a thought.
Conrad
Emil Wojcik
'64 356C Euro coupe
'78 MGB
'86 Jaguar XJ6 Series 3
'94 MB E420
'64 356C Euro coupe
'78 MGB
'86 Jaguar XJ6 Series 3
'94 MB E420
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Re: Rollbars - weld-in or bolt in? Recommendations?
A roll bar is part of a safety system. With a roll bar must come with a seat with a rigid, non folding back rest and a harness that will keep the driver from not impacting the bar during a collision.
A stock 356 seat or even a speedster seat is NOT an appropriate safety device!
Clearly a roll bar will add chassis stiffness. No question there. However, without the seat, the 5 point harness, the high density padding AND a helmet, a roll bar is just quick way to get blunt force trauma to the head.
A stock 356 seat or even a speedster seat is NOT an appropriate safety device!
Clearly a roll bar will add chassis stiffness. No question there. However, without the seat, the 5 point harness, the high density padding AND a helmet, a roll bar is just quick way to get blunt force trauma to the head.
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Re: Rollbars - weld-in or bolt in? Recommendations?
++1
< Jeff >
Registry Member Since 1978
1963 356B T-6 Super 90 Coupe
2009 997.2 Carrera S
2015 958 Cayenne diesel-1 & 2015 958 Cayenne diesel-2
Registry Member Since 1978
1963 356B T-6 Super 90 Coupe
2009 997.2 Carrera S
2015 958 Cayenne diesel-1 & 2015 958 Cayenne diesel-2