Can You Have a Roll Cage in a Streetcar

Reader
9/16/09 1:23 p.m.

Over the years, I've read many opinions on different forums about the pros/cons of the safety aspects of running a Roll Bar in a car that sees double duty as a HPDE/TT ca and street use.

I personally would love to get some more in depth info on this topic and think it would make a great article as well.

I understand one of the critical safety aspects of having a roll bar in a street car is its proximity to your unhelmeted head (which is why I no longer have a Miata). However, in my RX7, I think there might be enough room to fit a roll bar that isn't up against the back of my head.

I also understand that once a roll bar is installed, it is important to upgrade the seat. I read of an incident at Lime Rock where someone in a Porsche went off backwards and broke their back and died when the stock seat gave way/flexed enough for their back to hit the roll bar. Upgrade to what kind of seat, I don't know...

Anyone with experience in this subject matter care to comment?

Does GRM think it an interesting enough topic to write an article?

Thanks.

I'd certainly be interested in reading a properly researched article about this. I'll probably have to downsize for a while at some point and some of the ideas I have for taking part in future events suggest that the car should at least have a roll bar, but it'll also have to double as a DD.

ddavidv SuperDork
9/16/09 5:31 p.m.

A roll bar by itself can be relatively safe depending on the application, and assuming you are mounting a proper seat with a back brace and using SFI padding. There's still a risk, but I think it's reasonable. I think there is a much larger risk with a full cage and the side bars next to your noggin.

yes, properly mounted, a roll bar is not much of a danger to you. A cage, without the proper padding AND a helmet is just asking for a concussion.. or worse.

As for the porsche and it's late driver. I can only assume that the car had a harness bar installed. A regular 4 point bar would not contact the back of the seat (maybe a bit on the side closest to the door) if it failed. A harness bar, which would be right across shoulder height, would bend the seat and you back like a pretzel if the seat failed

I would love to see an article about this. Hell, I even write and research it if I could figure out where to get the data.

Every time this comes up in other forums (and I think this one too) there are the: it's fine, no problem with a proper seat and harness and you will die a horrible head crushing death camps. I think with proper seats and harnesses and padding on the cage/bar you'll be fine. But I don't know where you would find the data to back that up.

I've always heard the inverse of this: never, ever run a 5-point harness unless you have a rollbar/cage. Assuming you do put the shiny side down, being able to flex your upper body can make the difference between walking away and a crushed skull.

FWIW, I run a 4-point bar in my DD 5.0 'vert with stock seats and belts.

A couple of threads I read recently as an example of some of the discussions that I've seen:

http://forums.pelicanparts.com/showthread.php?t=367299&highlight=roll+bar+safe+street

http://forums.pelicanparts.com/showthread.php?t=458321

There are many more like that on various forums.

I would also be interested in said article. I've wanted to put a roll bar in the 7 but was afraid because it is street driven regularly.

NYG95GA SuperDork
9/16/09 9:21 p.m.

I use a Kirk 4 point in my SM Neon, which I also drive on the street, and I feel safe about it. I have it padded, just in case.

I spent a lot of time researching rollbars/roll cages seatbelts and various harnesses as well as different types of seats for both track and street use. In my case I wanted to make myself and navigator as safe as possible and also had to make sure that whatever I did would be allowed at the various sanctioning bodies I run the car at now as well as ones I want to run with. I looked at the rules and regulations for NMCA,NHRA, ECTA, SCTA/BNI, SSCC, and NASA.

Then I gave them to the chassis shop I was having build the cage and seat supports to look over. After that we had a meeting to try to sort it all out and called or emailed the sanction bodies to try to come up with something that would satisfy all of the things I do now as well as events/speeds I plan on going. It was a huge pain in the butt. However I learned a lot and it really opened my eyes up to things I'd done in the past that were just plain wrong and actually made the cars more dangerous than stock!

I'll be happy to try to answer any questions I can and if I can't I might be able to provide the correct contact information for someone who can provide an answer. I couldn't find much information on safety equipment when I started so I wrote a build thread to document what I did and problems, choices etc along the way. http://www.pro-touring.com/forum/showthread.php?t=48151

ReverendDexter wrote: I've always heard the inverse of this: never, ever run a 5-point harness unless you have a rollbar/cage. Assuming you do put the shiny side down, being able to flex your upper body can make the difference between walking away and a crushed skull. FWIW, I run a 4-point bar in my DD 5.0 'vert with stock seats and belts.

If you run a Schroth 4 point with the ASM technology it's DOT legal and will allow your body to move enough not to be crushed in a rollover without a rollbar. I ran them till I installed a cage and non hinged seats. http://www.schrothracing.com/store/Tuning/rallye/rallye-4 Click the wave file link at the bottom of the page for a cool video of ASM technology

mad_machine wrote: yes, properly mounted, a roll bar is not much of a danger to you. A cage, without the proper padding AND a helmet is just asking for a concussion.. or worse. As for the porsche and it's late driver. I can only assume that the car had a harness bar installed. A regular 4 point bar would not contact the back of the seat (maybe a bit on the side closest to the door) if it failed. A harness bar, which would be right across shoulder height, would bend the seat and you back like a pretzel if the seat failed

I installed a hooker rollbar in a friends Fox body Mustang, if he gets hit from the side he's going to get rollbared in the head. I couldn't convince him to send it back and get a custom bar welded in. You would think because it was made just for that car it should be safe but it is not. He's more likely to get hurt than without the bar in any accident just because his head is in direct line with it and no matter how tight the harness is his head will hit it.

ddavidv wrote: A roll bar by itself can be relatively safe depending on the application, and assuming you are mounting a proper seat with a back brace and using SFI padding. There's still a risk, but I think it's reasonable. I think there is a much larger risk with a full cage and the side bars next to your noggin.

SFI padding is HARD! It's designed to be hit with a helmeted head. Without a helmet it's gonna really going to hurt. The soft non SFI padding is soft enough so you'll really contact the tubing hard. If you don't think so, get a piece and put it on a rollbar and smack it with a rubber hammer. Then think about your 20 lb head hitting it with the same force.

NBS2005 wrote: I would love to see an article about this. Hell, I even write and research it if I could figure out where to get the data. Every time this comes up in other forums (and I think this one too) there are the: it's fine, no problem with a proper seat and harness and you will die a horrible head crushing death camps. I think with proper seats and harnesses and padding on the cage/bar you'll be fine. But I don't know where you would find the data to back that up.

I ran into the same night/day attitudes. I ended up doing what I thought would be best for my application. In some ways it's far safer than stock. (catastrophic crashes) while in other ways its less desireable. (I'd probably still get a bruised cheek in a low impact crash) The decision of compromises has to be made by the owner/driver and potential occupants.

I can see both sides of the arguments but the biggest issue I've seen is partial jobs and incompatable components. A good example is something I did myself because I didn't know any better at the time. Non hinged buckets with 5 point harnesses and no roll bar. If the car gets upside down your neck or back gets crushed. A stock seat and factory belt is actually safer because the hinges in the seat are designed to break or fold forward.

Another issue that has raised questions lately is the use of modern seatbelts in older cars when used without an airbag. I'm going to do some investigation on whether this is a good idea. Are the belts designed to be used only in conjuction with an airbag?

Rad_Capz wrote:

mad_machine wrote: yes, properly mounted, a roll bar is not much of a danger to you. A cage, without the proper padding AND a helmet is just asking for a concussion.. or worse. As for the porsche and it's late driver. I can only assume that the car had a harness bar installed. A regular 4 point bar would not contact the back of the seat (maybe a bit on the side closest to the door) if it failed. A harness bar, which would be right across shoulder height, would bend the seat and you back like a pretzel if the seat failed

I installed a hooker rollbar in a friends Fox body Mustang, if he gets hit from the side he's going to get rollbared in the head. I couldn't convince him to send it back and get a custom bar welded in. You would think because it was made just for that car it should be safe but it is not. He's more likely to get hurt than without the bar in any accident just because his head is in direct line with it and no matter how tight the harness is his head will hit it.

I put autopower bars in my fiat spiders. I would have to reach back way behind the seat to even touch it when sitting. I wonder why the hooker rollbar is so far forward?

mad_machine wrote:

Rad_Capz wrote:

mad_machine wrote: yes, properly mounted, a roll bar is not much of a danger to you. A cage, without the proper padding AND a helmet is just asking for a concussion.. or worse. As for the porsche and it's late driver. I can only assume that the car had a harness bar installed. A regular 4 point bar would not contact the back of the seat (maybe a bit on the side closest to the door) if it failed. A harness bar, which would be right across shoulder height, would bend the seat and you back like a pretzel if the seat failed

I installed a hooker rollbar in a friends Fox body Mustang, if he gets hit from the side he's going to get rollbared in the head. I couldn't convince him to send it back and get a custom bar welded in. You would think because it was made just for that car it should be safe but it is not. He's more likely to get hurt than without the bar in any accident just because his head is in direct line with it and no matter how tight the harness is his head will hit it.

I put autopower bars in my fiat spiders. I would have to reach back way behind the seat to even touch it when sitting. I wonder why the hooker rollbar is so far forward?

I put an Autopower bolt in my P car and it not a problem either but check out this location of the Hooker in a Fox. Oh,... and NO I DIDN"T DO THAT BATTERY SET UP !!!!!! LOL

that hooker setup... I would not drive in that WITH a helmet and padding. it is dangerous no matter how you look at it

1320 New Reader
9/17/09 3:19 a.m.

I have some experience in this. I ve built a fair share of street bars and cages for drag cars, and few that turn corners. I also have experience in offroad, and sand cars.

A "street" bar or cage is a lot different and substantially more dificult ussually to fabricate and install. Probably 90% of the cars I see, no matter what racing it does, I see easy improvements ussually and some common mistakes. Most racing regs are written well, but few are followed well. Then there are unsantioned cars, like sand rails. You want scary........I mean absolute retarded. 99.9 % of all sand cars are built poorly, designed poorly and just plain dangerous. The biggest by far mistake in most cars is the belt install. (primarely sand cars but not limited to them).

The shoulder belts do NOT hold you down in the seat. They should be at or slightly above youre shoulders to there attachment point. Most seats with cut outs for belts can only be use for kids or pretty short people. If the belt goes over your shoulder and down thats bad. The lap belt is what holds you down in the seat. The shoulder belts hold you from going forward. If the belt attaches below your shoulder, then you get compressed as the belt shortens when your body mass pulls on the belt in an impact.

Cages, and bars....well, in street cars, you have to go to great lenghts to get the bars away from your body (head). Ive cut body braces, removed dashed, taken windshields out, etc etc, to recess, move bars away further. If your held in a well braced seat, your head probably shouldnt be able to get to a bar. Some you just cant get that far away. and yes they are dangerous. I ve seen many sand car accidents, and deaths that could have been different with 20$ in steel in the right places.

Braces, gussets etc.....if kept intact and the body stays in the seat, the body can take some pretty serious g forces and survive. Its the blunt force trauma from hitting things that kills you.

It really depends on the car model in question how much interference there is for a street driven caged car.

Custom fit - built by a builder knowledgeable of the sanctioning rules of the cage you want - can optimize streetability. Does not mean it is safe in all accident conditions.

Cages built to make every sanctioning body happy is darn near impossible.

Nice battery install by the way

ddavidv SuperDork
9/17/09 5:17 a.m.

Rad_Capz wrote: SFI padding is HARD! It's designed to be hit with a helmeted head. Without a helmet it's gonna really going to hurt. The soft non SFI padding is soft enough so you'll really contact the tubing hard. If you don't think so, get a piece and put it on a rollbar and smack it with a rubber hammer. Then think about your 20 lb head hitting it with the same force.

I disagree. The SFI padding, helmet or not, is going to be more effective. It takes very little effort to compress standard Pep Boyz padding. The purpose of the padding is to keep your squishy bits from contacting solid, unbending steel. In a wreck with nasty g-forces, I think it is far too easy for your melon to fully compress standard padding and reach the metal bar. I'm not saying SFI padding is going to be 'safe', but far safer. Additionally, it is still going to be safer than the standard hard plastic bits snapped over a metal body panel like a stock vehicle has. The added danger is in the round tube with a more precise impact point than a flat panel.

It would certainly be nice to see an actual study on this, but there really has been no call for it. How many people out there really drive rollover equipped cars on the street? Who would pay for such a study? I think we're stuck with our own speculation on the issue.

I was always under the impression, if you have a rollbar you should also have quality fixed back seats and harnesses.

All 3 or nothing, since they work in concert together.

Jack SuperDork
9/17/09 9:17 a.m.

I have an autopower bar in my TR8. Fortunately, the main hoop is set pretty far back from the seat back, but I'm still going to pad the hoop. having seen videos of accidents, heads fly around quite a bit more than one would expect.

jack

ddavidv wrote:

Rad_Capz wrote: SFI padding is HARD! It's designed to be hit with a helmeted head. Without a helmet it's gonna really going to hurt. The soft non SFI padding is soft enough so you'll really contact the tubing hard. If you don't think so, get a piece and put it on a rollbar and smack it with a rubber hammer. Then think about your 20 lb head hitting it with the same force.

I disagree. The SFI padding, helmet or not, is going to be more effective. It takes very little effort to compress standard Pep Boyz padding. The purpose of the padding is to keep your squishy bits from contacting solid, unbending steel. In a wreck with nasty g-forces, I think it is far too easy for your melon to fully compress standard padding and reach the metal bar. I'm not saying SFI padding is going to be 'safe', but far safer. Additionally, it is still going to be safer than the standard hard plastic bits snapped over a metal body panel like a stock vehicle has. The added danger is in the round tube with a more precise impact point than a flat panel. It would certainly be nice to see an actual study on this, but there really has been no call for it. How many people out there really drive rollover equipped cars on the street? Who would pay for such a study? I think we're stuck with our own speculation on the issue.

David, I think we're in complete agreement but perhaps I didn't get it written well. I just wanted to get across to people who had never felt it that the SFI padding is not as compressable as you might think it is. You can not compress it by squeezing it with all your strength. When I recieved mine I was surprised at how hard it is.

It is indeed too easy for your head to compress the squishy padding to the bar. I have the SFI padding anywhere my head could possibly impact and the squishy stuff on the rest of the areas where arms and legs can hit.

Here's a couple pics of what we're talking about for those who may never have seen the different paddings close up. Squishy non SFI first and the SFI stuff below. Although the SFI padding comes with double stick tape it still needs to be ziptied to prevent it from moving during an impact.

That is the stuff... SFI high density padding @ $16 for 3'

z31maniac wrote: I was always under the impression, if you have a rollbar you should also have quality fixed back seats and harnesses. All 3 or nothing, since they work in concert together.

Yes that still holds true in most (if not all) cases.

A hinged seat might break during a rear impact. if it does the non retractable shoulder harnesses will fall to the sides and aren't going to help you at all on the rebound and your head could strike the bar.

Harnesses are required because regular seat belts don't hold you solidly enough to prevent your head from striking the bar in a rollover. I've watched a lot of crash videos and it's amazing how far your body parts move even while belted or harnessed in.

While on the subject. Using only 4 points of a 5 point harness is very dangerous because of the submarining effect. I know I was guilty of doing that in a couple of my cars because it was such a pain to use the sub belt every time I got in just to run to the store or whatever. After seeing videos of submarining that occurs if you don't use the sub on harnesses designed to be used with them I stopped and now use all points every time I get in the cars.

Can You Have a Roll Cage in a Streetcar

Source: https://grassrootsmotorsports.com/forum/grm/articleinfo-request-roll-bar-in-a-street-car/14131/page1/

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