Jump to content

Cage DOOR-BAR design, FIA vs US


davidfarmer

Recommended Posts

David, do you know what the specs are on the new driver's side bars for WC? For example, do they all have to be 1.75x.095 or can the straight tubes be be lighter or vice/versa? How many straight tubes required and must they be an x? Also, do the "nascar" portion of the bars have to attach the main hoop and a-pillar tubing or can they attach to the straight tubing?

 

thanks,

-V

Link to comment
Share on other sites

I don't have the specifics V, but all mandatory tubes must be the same diameter and wall thickness tubing.

On the STaSIS cars, which were built by Audi Sport, they look like somebody originally had X bars, then decided later to add "NASCAR" bars. my memory's a little foggy, but I believe both sets of tubes attach to the main and front hoops.

Link to comment
Share on other sites

you can download the rules from SCCA, but I'm pretty sure the bars have to all be the same (usually 1.75 x .095), and I KNOW that they all must attach to the fron and rear main hoops. So basically, your going to have around 5 separate tubes in each door to be 100% legal in World Challenge

Link to comment
Share on other sites

I was talking to Jim Pantas this weekend and he brought up a good point. He runs NASCAR bars for one simple reason, his elbows hit the "X" brace. If you are seriously worried about deforming the bars due to reduced tensil strength, run a 4 bar setup. If you crush a 4 bar design, you have a lot more to worry about and the simple X brace probably wouldn't fare any better IMO.

Link to comment
Share on other sites

  • 2 weeks later...

Coming from a NASCAR background, I can say this...I have been t-boned before in a NASCAR Stock Car and I am glad it had 4 doors bars instead of an "X". One thing that has not been mentioned above (unless I missed it) is that NASCAR racing, whether local or Nextel Cup, is technically a contact sport. Contact is expected and most of the time allowed in Nascar racing. If there was as much contact in the twisty racin', then yes, door bars similar to the Nascar design would probably be required. I just don't think FIA, NASA SCCA and others think that t-boning is common. When I build my car, I will have NASCAR style door bars. For one, I am used to getting in and out of a car with those style bars and two, I just feel that it is safer. No, I don't think I will ever be t-boned, but if I did, I would much rather have 3 or 4 door bars than just the NASA required 2.

Link to comment
Share on other sites

Davidfarmer,

 

Just curious, I have a good friend from back east that was involved many years racing both Nascar and other venues, by any chance are you related to "The" Farmers gang from the south or do you know Curtis or Red?

Link to comment
Share on other sites

  • 10 years later...

Bringing this thread back up from 10 years ago. Anybody else have thoughts they would like to bring to this discussion?

 

I'm thinking about putting a roll cage in my 240sx but I'm stuck on choice of door bar. I do like Nascar door because of the room and ease of jumping out of the vehicle in an emergency but in my car they would have an s-bend. I would like to choose which is more safer on a side impact.

Link to comment
Share on other sites

  • 4 months later...
I'm thinking about putting a roll cage in my 240sx but I'm stuck on choice of door bar. I do like Nascar door because of the room and ease of jumping out of the vehicle in an emergency but in my car they would have an s-bend. I would like to choose which is more safer on a side impact.

 

No S bends. One alternative is to leave the factory door impact beam in place and the pyramid style X-bar where as far into the door as you can. I'm assuming your gutting the doors if you're putting a cage in.

 

Read the "Cage Design" thread at Corner Carvers.

 

http://www.corner-carvers.com

Link to comment
Share on other sites

  • 4 months later...
  • 1 year later...

I have pretty stopped building NASCAR style bars. You must remember for the NASCAR door bars to be at its ulitimate effectivness is needs to attach the uprights to the 4x2 rail in the frame. Can't do that in a uni-body car but could attach them to a lower sill bar. Still wouln't be as effective but does provide extra protection. remember lower sill bar could be close to the left side seat frame. 

FIA has spent a lot of money testing the X door bars and has had really good results. I use a lower sill bar, 2 bar X, a pillar support tube and a tube gusset from main hoop to a pillar bar along with the appropriate sheet metal gussets. great for side impactx frontal and roll over. 

Link to comment
Share on other sites

  • 3 months later...

I think there are merits to both approaches.  I guess this is why I am willing to have a bit extra weight in my car where the X is a tension piece if hit and triangulates well.  I have another couple bars on the outside to allow a bit of crush zone.  This is also a tube frame car.  

driver side2.jpg

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...