Cage FAIL

[BlueVelocity]

http://jalopnik.com/5390934/mustang-cover-boy-tries-to-corner-flips-over-tire-wall

Said to be an Autopower 4 point bolt in. I've said once and I'll say it again, that's not a cage!

[Josh Warriner]

Some people want to be safe. Other people just want to pass tech (although I didn't think the Autopower would pass anywhere).

[Mirage]

First hand instance where the floor pan isn't a good bolt-in mounting point.

[JeremyVR-4]

Ohhh, man! Did the driver walk away or was he be-headed? That's also a failure on the officials behalf from a tech standpoint too! Going cheap on a cage is just foolish.

[D Walker]

Actually, it doesnt look like an Autopower "race" cage as there is no diagonal bar to be seen. My guess is its one of those "appearance" cages put out over the past few years that are just for looks and have no place on any race track anywhere. This guy was more than likely at one of the very popular "track day" or "club day" events where there is no tech beyond that the car isnt visibly leaking fluids and likely no one even looked at the car. I have said for some time that while the HPDE style event has a place, these club days where they are letting guys out on the track with little or no safety equipment in these cars and even less supervision is going to get someone killed.

[Cloud]

The cage was fine. If you actually look at the pictures and read it, the cage punched through the floorboards. It didn't tie into anything structural and just pushed it through the floorboards, you can see the mounting points about a foot through the floor in the upside down pics. The tubing is also pretty undersized for that heavy of a vehicle, and beyond that it isn't braced. That is about the size of the roll bar I'm putting in the miata, with better (hard) mounting points, and 1000 to 1500lbs less weight. To call that a 'cage' is a bit of a misnomer, it's just a braced roll bar like you would find in a convertible, except it's made wrong... as a joke ;)

[D Walker]

Its not even a rollbar, since without a diagonal brace its nothing but for show.

[Cloud]

Well, it looks like it has rearward bracing to me in those pictures which means it will actually stop stuff, not as well as rearward and diagonals, but it definitely offers some decent protection.

[Wazzelby]

Wow, and I was gonna buy a 4 point bolt in cage from a guy in the springs this week too for the eclipse..... I think I'll just hold off on that now...

[Cloud]

A bolt in cage isn't necessarily a bad thing, it just has to bolt to something useful like a reinforced strut tower rather than a thin ass floorboard.

[BlueVelocity]

A bolt in cage isn't necessarily a bad thing, it just has to bolt to something useful like a reinforced strut tower rather than a thin ass floorboard.

I'm not really sure about them. In my lifetime, I've seen 3 of them that were actually put to the test in a racing scenario. All 3 have failed to some degree. They pulled the backing plates through the floor, or the bolts have pulled through the backing plates, or one form or another of failure. The problem isn't the material used for the tubing, it's how the materials are attached to the vehicle. There just isn't any way of doing it properly for a secure attachment that will dissipate the load in a multi-angle impact.

Quick poll: Has anyone ever seen one in a crash that worked?

[rigby]

...The problem isn't the material used for the tubing, it's how the materials are attached to the vehicle. There just isn't any way of doing it properly for a secure attachment that will dissipate the load in a multi-angle impact.


Which brings up the question of how are the real (ie: non-bolt in) cages securely attached to the vehicle, Erron? I stopped working on my DSM build up before doing a cage but I thought that welding to floor plates and hardpoints on the body would be sufficient. Seems like that's kinda the same thing if the bolt-in were done correctly. What am I missing?

[Cloud]

Ok, so if you are going to tie into a crappy spot, you need a huge mounting plate. If you tie into existing spots that do NOT suck then you are doing good. The one for the miata is tied into the factory bracing behind the rear seats and triangulates back to the strut mounts. Without diagonal bracing, and smallish 1.5" tubing, it did not deform in a rollover. This is an example of PROPERLY bolting in a roll bar. Not all vehicles have good mounting points for a bolt in bar. Floor boards are not one of them unless you are doing a full cage and have forward supports into a solid area as well.

[BlueVelocity]

Great question Steve. This is different for every car, but lets talk DSM's. For one, by keeping the interior you essentially have a cage within a shell. This allows for a lot of room before the cage comes into play which can quickly enter the cockpit area. About 4 inches where the interior is located. This is not ideal. What you really want to do is get the cage out as far as you can and tie into multiple spots, not just the base plates. Technically, this adds to "points" of a cage. For instance, if you can take the vertical sections of the main hoop and not only weld to the plates but also along the vertical parts and tie it to the pillars you now have more area to disperse the impact load. You can also do the same thing along the sil bars that run next to the set. In short, the more places you can tie into the body structure, the less load each point has to endure during an impact. In a uni-body car there aren't any old-school rails. The floorboards are essentially spot welded and body glued into place. If you must be on the floor, box in this location to the stronges parts you can find, typically the door sills and uni-body box rails. You get the idea here, the more load you can disperse through larger surface areas will increase the structural impact strength.

Here's a great thread I was part of a while back that will really shed some light on the subject. (Jake's car, was Justins car in which I built the cage for)

http://www.evo-tech.net/forums/showthread.php?t=364

[Project2G]

Wow, and I was gonna buy a 4 point bolt in cage from a guy in the springs this week too for the eclipse..... I think I'll just hold off on that now...

Thatwas my old roll bar if your talkiing about Clark. I sold it and went with the AutoPower 4 point lol.

[Wazzelby]

That might have been him. He was trying to sell it for $200. I decided to wait and go with a real weld in cage instead. Plus with my wife's recent surgery, I'm trying not to buy frivolous things.

[Supra98st]

Wow, that is crazy!