Rollbars - weld-in or bolt in? Recommendations?

For those who couldn't care less how their 356 left the factory!
Post Reply
Message
Author
David Maxwell
356 Fan
Posts: 53
Joined: Tue Dec 23, 2014 5:58 pm
Location: New York City

Rollbars - weld-in or bolt in? Recommendations?

#1 Post by David Maxwell »

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?

User avatar
Glen Hamner, Jr
356 Fan
Posts: 491
Joined: Thu Mar 27, 2008 4:16 pm
Tag: '63 S/R project, '80 911SC, '11 Cayenne
Location: San Antonio environs, TX
Contact:

Re: Rollbars - weld-in or bolt in? Recommendations?

#2 Post by Glen Hamner, Jr »

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.

User avatar
Craig Richter
356 Fan
Posts: 1305
Joined: Thu Dec 15, 2011 9:01 pm
Location: San Miguel de Allende/Traunkirchen

Re: Rollbars - weld-in or bolt in? Recommendations?

#3 Post by Craig Richter »

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.
 

User avatar
C J Murray
356 Fan
Posts: 9161
Joined: Fri Oct 23, 2009 7:24 pm
Location: 30MI WEST OF PHILA
Contact:

Re: Rollbars - weld-in or bolt in? Recommendations?

#4 Post by C J Murray »

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...
IMG_1137.jpg
'57 Speedster
'59 Sunroof
'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion

Jeffrey Leeds
356 Fan
Posts: 1280
Joined: Sun Apr 20, 2008 4:57 pm
Location: Northeastern MA

Re: Rollbars - weld-in or bolt in? Recommendations?

#5 Post by Jeffrey Leeds »

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
< 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

Conrad Carter
356 Fan
Posts: 436
Joined: Tue Aug 05, 2014 9:54 am
Tag: Let's be careful out there!
Location: Durham, NC

Re: Rollbars - weld-in or bolt in? Recommendations?

#6 Post by Conrad Carter »

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

User avatar
Emil Wojcik
356 Fan
Posts: 1521
Joined: Tue Mar 25, 2008 7:20 pm
Location: Metuchen, NJ

Re: Rollbars - weld-in or bolt in? Recommendations?

#7 Post by Emil Wojcik »

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
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.
Emil Wojcik
'64 356C Euro coupe
'78 MGB
'86 Jaguar XJ6 Series 3
'94 MB E420

Adam Cultraro
356 Fan
Posts: 74
Joined: Wed Jan 06, 2016 12:09 am

Re: Rollbars - weld-in or bolt in? Recommendations?

#8 Post by Adam Cultraro »

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.

Jeffrey Leeds
356 Fan
Posts: 1280
Joined: Sun Apr 20, 2008 4:57 pm
Location: Northeastern MA

Re: Rollbars - weld-in or bolt in? Recommendations?

#9 Post by Jeffrey Leeds »

++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

Post Reply