Street roll bar failure on a race track.

Belgian1979vette said:
racervette69 said:
portaw.jpg



Just something to think about when leaving the proper bracing out of a roll bar. This was a bolt in four point street bar. Rest of the pictures below.

http://www.motorauthority.com/pictu...ver-of-5-0-mustang-wrecks_gallery-1#100232524
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Look better, go faster...they look better indeed.:pprrtt:
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If you look closely, you can see the shaming of a magazine - ever read an article and listen to their "I'm better than you" attitude when it comes to parts and install.... that picture is the one that let all the air out of their ego :bump:
 
None the less, to crush in a roof with even a crappy roll cage? Must have been a hell of an impact don't you think?


Maybe you've seen this one, front suspension failure. Check out his arms, the passenger seat-belt, etc... in slow-mo. I think I saw a license plate fly by. Need to stow and remove beforehand! Then maybe do the Danica Patrick Indy style tuck of the arms.
[ame]http://www.youtube.com/watch?v=e-9XSOM5eIo[/ame]

[ame]http://www.youtube.com/watch?v=95evw68W2LU[/ame]

Ralphy
 
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Ya but thats a unibody. The legs of a roll bar wouldnt push through the frame rails of a c3.
 
Ya, well the roll bar didnt fail the floor failed. You have to weld a fat plate to the floor when youre caging a unibody, to disperse the load.
 
You mean something like this? Stronger position, wider and able to absorb energy over a greater area. If that's the size plate to the right, it's almost all show and no go.

mm_vs_ap.jpg
"Heres a picture of the proper bolt in roll bar mount vs the autopower mount which was used in the mustang..."
http://forums.rennlist.com/rennforu...n-forum/618481-cage-time-for-the-928-a-2.html


Automotive version of a WWE style body slam.
medium_a90a14951a77899272ca5c4de8bdc69c.jpg
 
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The small Triumphs I race were known for doing that so you'll typically see a transverse cross bar welded between the uprights to help spread the load over the entire floor pan. Pipe bends in the middle but stays up:bonkers:
 
Ralphy said:
You mean something like this? Stronger position, wider and able to absorb energy over a greater area. If that's the size plate to the right, it's almost all show and no go.

mm_vs_ap.jpg
"Heres a picture of the proper bolt in roll bar mount vs the autopower mount which was used in the mustang..."
http://forums.rennlist.com/rennforu...n-forum/618481-cage-time-for-the-928-a-2.html


Automotive version of a WWE style body slam.
medium_a90a14951a77899272ca5c4de8bdc69c.jpg
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nice fabbing on the left, right is just silly...still don't understand the bolting in. The left structure if welded in would be nuclear blast proof... if the bolts shear you still have issues
 
Here's a belt and cage failure. Number of studies where done on this accident. See if I can dig them up. You just cant predict what will happen racing. How much impact your going to have and where. Pl*** was my hero, followed him for a number of years. Still no one is for sure what happened. Looks like he never lifted. Medical, suspension??

http://youtu.be/aYupaXjYnP4
 
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hate arm chair quarterbacks - but who thought that bracket on the right would do anything but fold in a crash? only air holds it up, and it provides awesome leverage to rip that bracket out of the floor when it hits...

mm_vs_ap.jpg
 
SuperBuickGuy said:
mm_vs_ap.jpg
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How much weaker could a bolt in bar like the one on the left be compared to bar welded on? The shear or tensile strength of 4 large grade 8 bolts has got to be somewhat close to a perimeter welded plate, no? Everyone seems to hate on bolt in bars, but when properly mounted (to the frame!) I dont see how it could be that much stronger. Hell, the lap belt on my car is riveted to fiberglass! Id be willing to bet that would go before a proper bolt in bar does.
 
I think bolt in bars of this type are sold primarily with the thought to buyers as, "hey I can always remove it." However a bolt weakens the tubing can loosen and cause a smaller shear point than a weld.

Some cases it's almost a must, such as.
ac-cobra-continuation-432898-3.jpg



YIKES!
picture019br.jpg


All Show
images


Not me, what's worse the angle iron or the two bolts? Top left.
dscf07151.jpg
 
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I remember a guy from another site who had a bolt in show cage....those fools all thought he walked on water, his reasoning for the bolt in cage was that during a safety inspection his government might not like it....but they wouldn`t notice the big honkin blower sticking up through the hood blocking his vision?????
 
vette427sbc said:
SuperBuickGuy said:
mm_vs_ap.jpg
Click to expand...

How much weaker could a bolt in bar like the one on the left be compared to bar welded on? The shear or tensile strength of 4 large grade 8 bolts has got to be somewhat close to a perimeter welded plate, no? Everyone seems to hate on bolt in bars, but when properly mounted (to the frame!) I dont see how it could be that much stronger. Hell, the lap belt on my car is riveted to fiberglass! Id be willing to bet that would go before a proper bolt in bar does.
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I have no problem with bolt in cages, they are not as strong as a fully welded plate, but properly installed with decent plates and they shouldn't be a problem. My problem is the roll cage hanging in mid-air - it'll rip the mount out of the floor then go through the floor. I'm sure the guy putting it in said "well, even if it does, it still provides safety." I disagree with that line of thinking because what used to be mostly soft surfaces on an interior now could break and damage you.
 
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