Race Car Tech Discuss anything related to road racing and auto X.

does a cage stiffen the body?

Old 05-27-03, 12:18 AM
  #1  
Rotary Enthusiast
10 Year Member
Thread Starter
 
Join Date: Mar 2002
Location: Tuscaloosa, AL
Posts: 1,430
Likes: 0
Received 0 Likes on 0 Posts
does a cage stiffen the body?

will a cage act kinda like a strut bar? Whats type of cage would I need if ran 10's (1/4 mile). Also Im very conserned about the wieght of a cage, any ideas? If anybody has a pic of a cage in a fd please post it. thanks..
93redFD is offline  
Old 05-27-03, 12:35 AM
  #2  
Car>woman
10 Year Member
 
3isacharm's Avatar
 
Join Date: Jul 2002
Location: Woodstock, GA
Posts: 967
Likes: 0
Received 0 Likes on 0 Posts
if done properly, it will tie together the chassis and make it more rigid. it's like a giant strut bar, that can stiffen the chassis and save your *** at the same time.
3isacharm is offline  
Old 05-27-03, 12:57 AM
  #3  
I'll blow it up real good
10 Year Member
iTrader: (1)
 
RX-Heven's Avatar
 
Join Date: May 2001
Location: San Francisco, CA
Posts: 2,390
Likes: 0
Received 0 Likes on 0 Posts
Some people consider the factor of safety from a cage as a secondary bonus to stiffening the chassis for improved handling. These are usually the people who havn't been involved in serious incidents though.
RX-Heven is offline  
Old 05-27-03, 02:15 PM
  #4  
trying to build a racecar
 
Travis R's Avatar
 
Join Date: Sep 2002
Location: Austin, Tx.
Posts: 579
Received 1 Like on 1 Post
If you are going to be running 10's then you will be required to have a cage and it will have to be NHRA legal. So that will dictate a lot of the design. But yes a good cage will definitely stiffen the chassis. A full cage, not just a roll hoop, will probably weigh over 100lbs.
Good luck
Travis R is offline  
Old 05-28-03, 06:39 PM
  #5  
Rotary Enthusiast
10 Year Member
Thread Starter
 
Join Date: Mar 2002
Location: Tuscaloosa, AL
Posts: 1,430
Likes: 0
Received 0 Likes on 0 Posts
Im not really worried about the track given me any problems about my time. The tracks here are "redneck" tracks. I have seen people get away with painting pvc pipe and wraping it in cushing and throwing it in the car and calling it a cage .
I most worried about saving my life and weight but was just curius if it stiffened the body.
This is a daily driven street car, so what type of cage would I need. I want something that looks good and wiegh not to much. I want to stay around the 100 lb thing.
Does anybody have any pics of a cage in a 3rd gen?? I would really like to see the cages first. thanks
93redFD is offline  
Old 05-28-03, 07:46 PM
  #6  
Rotary Freak
15 Year Member
 
Jerk_Racer's Avatar
 
Join Date: Feb 2001
Location: Okinawa, Japan
Posts: 2,149
Likes: 0
Received 0 Likes on 0 Posts
Sometimes cages can kill you. Make sure that your melon isn't even close to the bar if you get one that goes by that area. Even with padding on it, without a helmet if can bust your skull or worse.

The rest I'll assume you don't already have. Depending on local laws, see about getting a racing seat to lower your body in the car as low as the floor will let you go. With the cage you'll have a suitable place to hook up a 4 or 5 point harness. Schroth harnesses are the only ones that I know of that are D.O.T. legal. Even then, it might depend on the model of belt that you get as the entire lineup of their belts might not be D.O.T. legal.

If you get a cage, sometimes called a rollbar, that just just is a hoop with several mounting points that is all behind the passenger area then you will not have to worry about whacking your grape on the bar up there.
Jerk_Racer is offline  
Old 05-28-03, 08:06 PM
  #7  
Rotary Enthusiast
10 Year Member
Thread Starter
 
Join Date: Mar 2002
Location: Tuscaloosa, AL
Posts: 1,430
Likes: 0
Received 0 Likes on 0 Posts
yea i talk to guy that got in a wreck(rearended) and he busted his head becuase of the cage. Im not sure about the racing seats and harnesses. I know there are some goods/bads of harnesses but I really dont like the wayt they look. Is it possible to lower the stock seats?
93redFD is offline  
Old 05-28-03, 11:38 PM
  #8  
Newbie
 
Join Date: May 2003
Location: Surrey, BC
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
The cage I have is attached in 8 places. It weighs about 130lbs. Once the scanner is hooked up I will post a pic or two of mine.
racebunnie is offline  
Old 05-29-03, 06:08 AM
  #9  
Rotary Enthusiast
10 Year Member
 
Join Date: Oct 2002
Location: Fairfax, VA
Posts: 1,415
Likes: 0
Received 0 Likes on 0 Posts
after I installed a rollbar in my 85, I can jack up a rear corner of my car to swap a wheel, and do both rears at the same time... there just isn't any flex back there....

Dan
Lt. Dan is offline  
Old 05-29-03, 03:59 PM
  #10  
Senior Member
5 Year Member
 
Join Date: May 2003
Location: CHINO HILLS,SO CAL
Posts: 467
Likes: 0
Received 0 Likes on 0 Posts
does anyone have the m2 roll bar for fd. i have a sunroof model and wanted to know if anyone had the m2 and could send me some pics.
hyper7 is offline  
Old 05-29-03, 05:07 PM
  #11  
Rotary Enthusiast
10 Year Member
Thread Starter
 
Join Date: Mar 2002
Location: Tuscaloosa, AL
Posts: 1,430
Likes: 0
Received 0 Likes on 0 Posts
so how much for a 8 point cage?
93redFD is offline  
Old 05-29-03, 06:53 PM
  #12  
Has been.. hangin' around
10 Year Member
 
Silkworm's Avatar
 
Join Date: Mar 2001
Location: Milpitas, CA
Posts: 2,618
Likes: 0
Received 0 Likes on 0 Posts
For what? NHRA legal 10 second passes or road racing?

Jegs has NHRA legal (I believe, don't have their rule book handy) cages for the 2nd gen, didn't look to see if they have 3rd gen cages.

SCCA/NASA legal 8 points, Kirk or Autopower sell bolt in/weld in kits, or you can get a custom built cage.

Costs run from 300-400 on up.

PaulC
Silkworm is offline  
Old 05-30-03, 10:45 PM
  #13  
Living life 9 seconds at a time

iTrader: (2)
 
ErnieT's Avatar
 
Join Date: Feb 2001
Location: Abingdon, Md
Posts: 6,541
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by Travis R
If you are going to be running 10's then you will be required to have a cage and it will have to be NHRA legal. So that will dictate a lot of the design. But yes a good cage will definitely stiffen the chassis. A full cage, not just a roll hoop, will probably weigh over 100lbs.
Good luck
A 8pt. chrome molly cage only weighs 35lbs. and is legal for 9sec. timeslips.
ErnieT is offline  
Old 05-30-03, 10:47 PM
  #14  
Living life 9 seconds at a time

iTrader: (2)
 
ErnieT's Avatar
 
Join Date: Feb 2001
Location: Abingdon, Md
Posts: 6,541
Likes: 0
Received 0 Likes on 0 Posts
Also, one other point, the roll bar that M2 and Kirk racing sells is NOT NHRA legal. I've already discussed this with both places prior to getting a cage. They use tubing that isn't as thick as required by NHRA.
ErnieT is offline  
Old 05-31-03, 12:52 PM
  #15  
Senior Member
5 Year Member
 
DrifterFD3S's Avatar
 
Join Date: Feb 2003
Location: DALLAS TX
Posts: 582
Likes: 0
Received 0 Likes on 0 Posts
if its street driven, id suggest a four pt. roll cage. it only goes behind you, saveing your life and weight. going over the bars that go by the doors in an 8pt. (most of em any ways) is quite annoying after a while. a four pt. also makes the chassis quite stiff as well.
DrifterFD3S is offline  
Old 05-31-03, 01:19 PM
  #16  
Learned alot | Alot to go
10 Year Member
iTrader: (2)
 
CrackHeadMel's Avatar
 
Join Date: Apr 2002
Location: Rotaryland, New Hampshire
Posts: 4,233
Likes: 0
Received 0 Likes on 0 Posts
A 8pt. chrome molly cage only weighs 35lbs. and is legal for 9sec. timeslips.
ive hurd crommolly cages are light, but diddnt expect an 8pt to weight that little

got any link's to distributors?
CrackHeadMel is offline  
Old 05-31-03, 02:44 PM
  #17  
Banned. I got OWNED!!!
 
christaylor's Avatar
 
Join Date: Mar 2003
Location: Austin, Texas
Posts: 1,546
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by ErnieT
A 8pt. chrome molly cage only weighs 35lbs. and is legal for 9sec. timeslips.
I find that extremely hard to believe, since I just installed a 6pt bolt-in that weighed close to 100#'s. Chromoly, in the diameters required for a rollcage, is pretty hefty. I seriously doubt a "cage" made out of aluminum would even weigh that little.
christaylor is offline  
Old 05-31-03, 10:33 PM
  #18  
Living life 9 seconds at a time

iTrader: (2)
 
ErnieT's Avatar
 
Join Date: Feb 2001
Location: Abingdon, Md
Posts: 6,541
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by christaylor
I find that extremely hard to believe, since I just installed a 6pt bolt-in that weighed close to 100#'s. Chromoly, in the diameters required for a rollcage, is pretty hefty. I seriously doubt a "cage" made out of aluminum would even weigh that little.
Then you obviously arn't around too many drag racers. A cage weighing 100lbs? Are you filling it with concrete?! Go to a reputable fabricater and you'll see for yourself.
ErnieT is offline  
Old 06-01-03, 12:32 AM
  #19  
Rotary Enthusiast
10 Year Member
 
Join Date: Apr 2001
Location: North Hollywood, Ca USA
Posts: 1,289
Likes: 0
Received 0 Likes on 0 Posts
all racing sanctioning groups have different rules with regards to safety equipment. check the rule book of the sanctioning body(NHRA, NASA, SCCA, etc) before starting work on cages and the like. cages can vary dramaticly in weight by substituting a thinner walled chromoly tubing in place of the thicker walled DOM mild steel tubing. this is allowed in some racing groups and not others. SCCA and NASA don't let you use thinner tubing when using chromoly so there would be no weight difference, but the NHRA may allow the use of thinner walled chromoly when used in their required cages. read the rules and check with fellow racers in the series you intend to race in before starting any work.
tims is offline  
Old 06-01-03, 01:30 AM
  #20  
Banned. I got OWNED!!!
 
christaylor's Avatar
 
Join Date: Mar 2003
Location: Austin, Texas
Posts: 1,546
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by ErnieT
Then you obviously arn't around too many drag racers. A cage weighing 100lbs? Are you filling it with concrete?! Go to a reputable fabricater and you'll see for yourself.
I doubt they're reputable if they tell you an 8pt cage weighs 35lbs.... I'll go out an weigh the other Autopower cage I've got to be sure, but it can't weigh much less than that.

Did the NHRA make exhaust pipe legal for rollcages?
christaylor is offline  
Old 06-02-03, 12:03 PM
  #21  
trying to build a racecar
 
Travis R's Avatar
 
Join Date: Sep 2002
Location: Austin, Tx.
Posts: 579
Received 1 Like on 1 Post
Originally posted by ErnieT
A 8pt. chrome molly cage only weighs 35lbs. and is legal for 9sec. timeslips.
Can you tell me the tube diameter and wall thickness for this cage? This will obviously play a big part. The weight I listed was for approx. 60' of steel tubing, 1.5" dia. x .120" wall @ 1.769lbs/ft = 100.83 lbs, not including mounting plates or welding add rod.
60' in an FC should get you a main roll hoop, a rear "x" to the top of the rear struts, horizontal harness bar, over door bars, side impact door bars, halo, under dash, and two bars to go through the firewall to the front strut towers.
Travis R is offline  
Old 06-02-03, 07:34 PM
  #22  
Rotary Enthusiast
10 Year Member
Thread Starter
 
Join Date: Mar 2002
Location: Tuscaloosa, AL
Posts: 1,430
Likes: 0
Received 0 Likes on 0 Posts
wtf, this thread has gotn way over my head. I just wanted a cage so I can run 10s at the track and save my life .
crome moly deal seems light. Anybody have a clue about the cost?
Again I would like to see some pics.
93redFD is offline  
Old 06-03-03, 10:09 PM
  #23  
rsa
Full Member
10 Year Member
 
Join Date: Mar 2001
Location: Jersey Shore
Posts: 68
Likes: 0
Received 0 Likes on 0 Posts
Cost depends on material used, skill of fabricator, etc. There are pics of a legal chrome moly NHRA cage at www.msfabrication.com . Click on "93 RX7. That one also has swing outs on both sides.
rsa is offline  
Old 06-03-03, 11:59 PM
  #24  
Banned. I got OWNED!!!
 
christaylor's Avatar
 
Join Date: Mar 2003
Location: Austin, Texas
Posts: 1,546
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by Travis R
Can you tell me the tube diameter and wall thickness for this cage? This will obviously play a big part. The weight I listed was for approx. 60' of steel tubing, 1.5" dia. x .120" wall @ 1.769lbs/ft = 100.83 lbs, not including mounting plates or welding add rod.
100lbs is more like it. The more I think about it, the more impossible it would be for a full cage to weigh 35 lbs. A rear hoop, maybe, but not a full cage.

I'm not 100% familiar with NHRA specs, but it can't be that far off SCCA specs, which I am familiar with. And no cage I've ever installed, or helped install, has been anywhere near 35 lbs. All have been chromoly or DOM tubing.
christaylor is offline  
Old 06-11-03, 05:26 PM
  #25  
Newbie
 
Join Date: May 2003
Location: Surrey, BC
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by 93redFD
so how much for a 8 point cage?
I paid $110.CDN for the material and borrowed a tube bender from a guy at the racetrack then had my bf's brother weld it in. Not sure how much it would cost to have someone else do it but I don't think it would be as cheap.
racebunnie is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rx7jocke
Suspension/Wheels/Tires/Brakes
72
06-17-16 03:48 AM


Thread Tools
Search this Thread
Quick Reply: does a cage stiffen the body?


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: