Roll cage/bar Question

[Dave-ROR]

Originally Posted by dirtymax

I travel on a very dangerous road were cars routinely get flattened and people die. I have been looking at the Cusco 4 point and my worries have been the function of the rear air bag and if I can get enough padding on the rear bars to keep it safe for my kids

Little kids might stand a better chance in the back assuming they are in car seats that are secured however I would never suggest it.

You have to look at the forces involved in accidents and the amount of body movement that occurs even when properly using a 3 point belt. A padded bar will still kill someone. Not to be an asshole, but think of the odds of an accident and then consider the forces and finally how you'd feel if something happened to your kid because of your actions. I'm trying to make you think about it in depth.

I used to be one of those idiots with a cage in a street car (although it was mostly a track car but still) and it's something I would never do again. Clearly I didn't die, but I will be very up front and honest by describing my own actions as idiotic. Even then I didn't have back seats in the car but a cage with front seat driver/passenger is just as idiotic. I was young and stupid. (To be clear that was a 6 point with dash and door bars, not a 4 point roll bar which can be done safely on the street but still requires ALL of the safety gear.)

I have no idea what to tell you if you live in that dangerous of an area. Hell I'd move for your kids sake but assuming that's not possible I don't really have any suggestions about making your car safer. You are in a VERY safe vehicle as is and adding bars near passengers is NOT going to make it safer without the full system and it's going to be impossible to have more than a 2 seater with the full system of safety gear required to do it right.

[dirtymax]

I just had a friend die last week on that road and its nothing new so I'm sorry if you guys think I'm blowing this out of proportion. I can post the link if you like

[Dave-ROR]

Originally Posted by Racecomp Engineering

Mordor!

Seriously though, those who have been in this a long time know someone or has witnessed injuries or worse from improper safety prep. For example, a friend in high school had to have major plastic surgery after getting in an accident on the street with his roll cage equipped car.

- Andy

Here's one that a few people on this forum knew:

http://www.ft86club.com/forums/showt...ighlight=death

I know a bunch of people that were there, both on this forum and outside of it. This was on the track but the accident wasn't really THAT bad.. nor was it a rollover.

[Racecomp Engineering]

Originally Posted by dirtymax

I just had a friend die last week on that road and its nothing new so I'm sorry if you guys think I'm blowing this out of proportion. I can post the link if you like

No need to do that....sorry for your loss.

Sorry if we're harsh and I understand if some of this is new to you. Nothing wrong with asking questions...I'm glad you asked honestly because many DON'T and then bad things happen.

This is just one of those "seriously please don't do that" kind of thing that strikes a chord for many of us based on experience and the fact that some of us (not myself but Myles in the office) are instructors and ride in other's cars all the time.

- Andy

[Dave-ROR]

Originally Posted by dirtymax

I just had a friend die last week on that road and its nothing new so I'm sorry if you guys think I'm blowing this out of proportion. I can post the link if you like

I'm sorry to hear about your friend I didn't think that you were blowing it out of proportion but my opinion doesn't change.

I hope whatever changes need to happen to get control of that roadway/area will happen. It seems as though the drunk driver aspect could be controlled and I'd guess Cali is just as angry with lifted trucks as they are with lowered cars so there seems like there could be more enforcement there too.

Shitty though.

[dirtymax]

I certainly didnt want to hijack this thread and turn it into drama but my questions have been answered. Its a no go on the roll bar

[mrk1]

Originally Posted by Dave-ROR

Bolted is better than nothing. Although I add even bigger plates in on top and bottom (of the sheet metal of the car - I'm sure you knew what I meant but just in case others weren't clear) to help distribute load when using a bolted bar.

I don't know. Think about how easy that drill bit went through the floor pan. The strength in a welded in bar is being about to tie it into the strong rocker panel structures.

I have built numerous 4-6-8 point setups and I will never go back or build a bolt in piece again.

[mav1178]

Originally Posted by mrk1

I don't know. Think about how easy that drill bit went through the floor pan. The strength in a welded in bar is being about to tie it into the strong rocker panel structures.

I have built numerous 4-6-8 point setups and I will never go back or build a bolt in piece again.

Supporting argument:
http://jalopnik.com/5390929/mustang-crash-gallery/

-alex

[Dave-ROR]

Originally Posted by mrk1

I don't know. Think about how easy that drill bit went through the floor pan. The strength in a welded in bar is being about to tie it into the strong rocker panel structures.

I have built numerous 4-6-8 point setups and I will never go back or build a bolt in piece again.

This gets into a design conversation rather than a bolt in vs weld in conversation. If a 3x3 plate is used (and there are TONS of welded roll cages with just plates) then it's absolutely no better than a bolt in solution. Using a larger base plate (4x8/6x8/etc) is certainly not as good as boxing the mount to use multiple surfaces, including the rocker, but is still better than a 3x3 or 4x4 welded plate. I supplemented my bolt in bar's plates for this reason. Is it as good as the race cars boxed mounts? Of course not, but it's better than the default autopower mounts. At the end of the day, if it's mounted to a plate (bolted or welded), the size and load distribution of that plate has to be sufficient, otherwise you get the wreck posted above in a high energy roll over. The failure in that mustang and other times when this has happened was the sheetmetal, not the bolts/etc.

That mustang is of course a lot heavier and faster than our cars and appears to have very small plates.

[mrk1]

Originally Posted by Dave-ROR

This gets into a design conversation rather than a bolt in vs weld in conversation. If a 3x3 plate is used (and there are TONS of welded roll cages with just plates) then it's absolutely no better than a bolt in solution. Using a larger base plate (4x8/6x8/etc) is certainly not as good as boxing the mount to use multiple surfaces, including the rocker, but is still better than a 3x3 or 4x4 welded plate. I supplemented my bolt in bar's plates for this reason. Is it as good as the race cars boxed mounts? Of course not, but it's better than the default autopower mounts. At the end of the day, if it's mounted to a plate (bolted or welded), the size and load distribution of that plate has to be sufficient, otherwise you get the wreck posted above in a high energy roll over. The failure in that mustang and other times when this has happened was the sheetmetal, not the bolts/etc.

That mustang is of course a lot heavier and faster than our cars and appears to have very small plates.

True it does comes down to the design. I have seen more poorly designed cages then good ones. If I remember I will measure the plates on the my car. I would guess the 3 plates are each about 5x5. Since its not a full cage i was able to get away with no box's.

[SuiSid3l]

Originally Posted by 7thgear

And if the car rolls, and IF the roof collapses on to you, the 3-point harness and your seat are designed in such a way as to allow your body greater movement to avoid getting crushed.

I'd REALLY like to know where people are getting this information?

[dradernh]

Originally Posted by SuiSid3l

I'd REALLY like to know where people are getting this information?

Well, it is harder to get crushed when your entire body has been stuffed into the passenger-side footwell because of the forces of the crash and the way the car rolled. Crushed from the top of the car collapsing, anyway.

[SuiSid3l]

Originally Posted by dradernh

Well, it is harder to get crushed when your entire body has been stuffed into the passenger-side footwell because of the forces of the crash and the way the car rolled. Crushed from the top of the car collapsing, anyway.

I'm just gonna put this information out there regarding anyone considering running a setup a street setup thats not OEM. Feel free to argue with me, I enjoy a good discussion.


The 3 point belt was invented in 1959 and at no point have I ever read that Bohlin designed it to keep from getting crushed in the event of a rollover. As far as I know it was used to support the upper body in order to alleviate rapid deceleration during a crash.

This is a little off topic but due to the nature of the discussion I wanna bring it up: 3 point belt vs 4 point and racing seat on the street.

The argument here is being crushed by the roof in a 4 point. Being crushed by the roof collapsing is not even the leading cause of death in the event of a rollover. Ejection is the leading cause. (fatalities in a rollover when your restrained period is only about 1 percent)

Secondly there are evaluations from reputable sources all over that advocate crushing from a roof cave in is rarely (if ever) even the issue with a rollover accident. Blunt force trauma from sliding around (like you do in a 3 point) or colliding with the roof (window, pavement, etc..) not it crushing you if often the cause of a rollover related deaths when the occupant was not ejected. Relevent sources:

What then are the causes of injury for non-ejected occupants in rollover
accidents? It is now generally agreed that the predominate mechanism is impact
and not crushing as has sometimes been thought in the past. This at least for
light vehicles (here light vehicles means under 10,000 lbs). The case with heavy
trucks is probably different as we shall see later however. We should then try to
clarify the differences between these two processes. Impacts are of relatively
short duration and involve only the striking and the struck objects. Crushing
suggests a slower process involving the crushed object and two other surfaces
or elements between which the object is crushed. Crushing can take all day,
even a slow impact is still a relatively quick bump or bang. The point is that we
should not expect to see and typically do not see a “tail print” in the floor pan of
every rolled vehicle in which an occupant is seriously injured. Light vehicle
occupants are not typically squeezed between the roof and the floor, nor do they
generally suffer any other type of crushing injury, they are hit. They experience a
“second collision” like some victims of planar accidents.

http://www.e-z.net/~ts/web-6-1-06/~d...Accidents3.pdf

And here is Joe Marko (hella credentials, look em up) quoted in modified magazine advocating the same exact thing

http://www.modified.com/tech/1309-di...r-safety-myth/

Not to mention side, front and rear impacts are better served in a 4 point harness. Here is an actual study based on front impact from a 3 point vs 4 point stating the added benefit of a properly designed 4 point harness.

http://www.ncbi.nlm.nih.gov/pubmed/17096257

That being said I'm not advocating you don't utilize your oem seat belts or that I'm right and everyone else is wrong. But a properly installed racing seat and a properly installed DOT certified harness is going to support you better in every other area aside from the slight possibility that the roof "crushes" you (the least plausible cause of death out of all car related fatalities).


Your OEM belts are percectly fined and the safety devices in your car are designed to aid the belt (side impact bags, etc) but by no means is that harness/seat less safe IMO (pretty much a safer better in every other aspect).

[dradernh]

Originally Posted by SuiSid3l

I'm just gonna put this information out there...

Points taken. My post was a little too smart-ass to be of any real use.

Joe has supplied all of my belts and chairs, explained to me the points raised in the Modified article, and shared quite a bit more. He's an excellent source of car safety facts and information, as are the people working for him. HMS is a very professional organization.