To Cage or Not to Cage??

[conekiller13]

In Oregon (where I'm at) if You've installed a 5 piont harness You are then required to wear that 5 point properly as part of the states seat belt law. It would seem if You put a cage in it would be kind of silly not to go the reat of the way with harnesses.

[jannes_z-28]

Building several racecars (full roundtube ProStock chassis) in my earlier days I would say that the main reason for a cage is not to protect the occupants of the car. From an engineers point of view the cage is there to connect the supensionpoints with the engine. The stiffer that is the better handling. Flex in chassis are powerrobbers.

The second reason is protection, but as had been said before, a cage can do harm to the driver if you are not well tied down and wearing a helmet. According to the rules (if I remember correctly) is that the top of your helmet should be below the lower part of the mainhoop. This will of course reduce the headroom, especially if you are tall. No sense for protection if your head is over the cage, right.

So if you want a stiff chassis you need a full cage.

Welded subframe connectors like the DSE will strengthen your car, but it will still flex.

It also depends on what you want to do with your car. If it is only to be streetdriven, but sometimes hard, I would say that you don't need the cage.
If you want to race with it, you might need it for the rules, you will need it for the strenght it will provide to the chassis.

To build a car is nothing but a major compromise.

Jan

[tndude]

Very well said Jan.

[Steve Chryssos]

I see gross generalizations stating do not under any circumstances install a roll cage in a street car because you might bang your head. How 'bout: Do not build a car capable of 150mph that does NOT have a roll cage--especially if it is capable of significant front end lift. Now there's a statement!! "Don't do it!!" is of no help at all. Instead there should be a thorough discussion about cage design that covers various topics including

-Bar Placement: By juggling seat height and side halo bar placement it is entirely possible to build 5" clearance between head and halo.
-Seat Type: I have a one piece FIA seat with significant side bolstering.
-Seat Mounting and Location. My one piece seat is rigid mounted to the cage and does not hinge.
-Padding Type http://lockracewrks.com/Products/Saf...BSCI/bsci.html available from BSR.
-Belt Type Mounting: Requires it's own discussion

Properly planned and executed, a roll cage will not hurt you and may very well save your ass--even on the street. I say do it--but do it right.


Oh! And keep your helmet in the car. You never know when it might come in handy

[conekiller13]

Very Well said Steve...............I knew I liked You for a reason.

[Marcus SC&C]

Steve`s right BUT there are a lot of ifs there. A lot of it depends on the driver. I`m a big guy,my hair usually just brushes against the headliner in most cars. Getting good bar to head clearance without a helmet just ain`t gonna happen in most cars. I`m a very firm believer in 6 and 8 pt. cages for the street (especially in subframe cars!). If the hoop in put in the proper location your head will never even get close and the low sidebars tie the chassis together through triangulation and provide side impact protection that most vintage muscle cars don`t have. Done properly the side bars aren`t much of an inconvenience at all.

When do you NEED a cage or roll bar? If we had put one in my sister`s 200hp 283/glide `67 Nova that got T boned she (and her best friend) might be alive today. The car squashed like a soda can. We had figured a cage would be "silly" because it wasn`t a fast car.... Marcus SC&C

[jonny51]

Sorry to hear that Marcus.I am a big fan of cages for many reasons.

[Steve1968LS2]

My new car has a full cage.. even belted in my head could hit the upper side bar but then again it could hit the edge of the roof too. the bar is thickly padded and hitting it would most likely do less damage than hitting the unpadded roof edge.

The rear hoop is far enough back so as not to be an issue and the door beam is protected because of the seat bolsters.

I may try to lower the seat some to give me even more room.

If done right a cage is fine.. if done wrong it can kill you.. seems simple enough to me..

Anyone remember the automatic seat belts on cars in the early 90's.. it would automaticly put on the shoulder belt but not the lap.. a few lazy people got decapitated and now that idea is gone.

Its called a safety SYSTEM for a reason.. all or nothing.. so buckle up

[PhaseShift]

This thread seems to be going in the direction that I would agree with, but I thought I would chime in as well.


I believe that the most critical factor here is the design. In pretty much every case on this forum (probably most others) we are all dealing with so many variables that it all comes down to one-off design. You have to really consider all of the variables that apply to your situation before you make the decision. How tall are you? How much room are you willing to give up? How good are you (or your shop) at precision fabrication? ... on and on.....

A lot of people who run a cage or roll bar do not like to use padding. The padding may not be a crash helmet, but it is a benefit in the event of a crash and head impact; mainly in the spreading of the load. You are still going to have the high g-force, but the load will be spread over a larger area and the risk of local fracture or shattering is not as high. Someone posted a link to some good roll bar padding; it is good stuff and stiff enough to be effective.

The other thing is about the safety restraint system. I do not mean to throw rocks here, but to me having a car with a cage and only wearing a lap belt or over the shoulder harness is just plain suicidal. Even a low speed accident could really plant your noggin against the cage (or column) in a big way.

[Payton King]

I might as well get in on this as well. I was concerned about a halo bar and it being close to my head. I opted for an eight point bar instead of the cage route. Main hoop(away from my head) braced with door bars to front of floor, rear bars to trunk area and bars from main hoop and cross bar to subframe connectors. I needed more safety because of HP level, but I did not need an all out cage. It will qualify me to run in the 10's at the strip, I can remove the door bars(bolted in) to cruise the streets and bolt them back in for the occasional track day. If I need to go open road racing then I feel a full on cage is a must.

With all of that being said. Steve's new 68 as a cage certified to run 8's at the strip and his Halo bar is padded. I would rather hit that padded halo bar in a crash than my head on the roof seal. Obviously, a full cage is going to give more protection than my set-up...just pad the halo or any other bars that you could come in contact with.

I went my route by being honest with the use of my car. 80% street and 20% track events with enough horsepower to get me in trouble at either place.