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Domino
09-16-2002, 11:31 AM
I'm starting the cage build process (very excited). I'm meeting with my fab this week to take the measurements etc. He has some ideas and I have some questions regarding placement of the points and associated connections. Any thoughts/comments would be greatly appreciated. My questions are as follows:
1. What's the best place for the front down-tube? In front of the dash and A/C vent? (closest to driver) Down trough the A/C vent? Or following the angle of the pilar, close to the glass, between the windshield and dash (notch cut into the back of the dash and furthest from driver). I'm most likely having the last one; easier entry/exit and more cave-in protection.
2. What's the best place for the main hoop? Welded to the lowest part of the floor or 4 inches higher on the "hump" where the cargo juck used to be? I don't have my seat yet so I don't know how much clearance there will be between the seat back and the horizontal bar.
3. What's the best place for the rear braces? On the wheel well closet the the shock tower? (I like this is the weakest part) The floor where the wheel well attaches to the body and adjacent to the shock tower? My only concern about attaching it to the floor is that it will create a 45 degree angle from the actual body of the car (measured from the rear quarter panel glass to the brace).
4. I won't be incorporating NASCAR bars yet as I will have to drive it and need the glass. What is best? An X bar or two horizontal bars with two perpendicular pieces in the middle connecting them? (I see now per the GCR that a X bar won't be legal. I must have misread it)

5. I know the minimum weight for the CRX is 2140. The cutoff for using 1.50 x .095 DOM material is 2200 lbs. I take it a lot of people use 1.50 x .120 tubing then. 60 lbs is a small margin and I don't think I will able to get it that close. Since I don't have a scale and it will be driven on the street. Oh well .120 it is then.

Thanx.


[This message has been edited by Domino (edited September 16, 2002).]

jc836
09-16-2002, 01:18 PM
I'm going to strongly urge you to take a long look at the GCR pages 144-150 to start with. Then you need to read the latest info in FastTrack about tubing. You are not allowed to use ERW tubing any more. Next, might I suggest that you and your fabricator contact Mark Stewart at KIRK Racing and see what cage he has available for your project (there are other makers, but he is very up on the rules). That is the cage my fabricator put in for me.
Mounting points on the KIRK have the forward down tubes butting up against the front edge of the dashboard. The MAIN hoop is attached to the floor directly in front of the kickup/hump. The horizontal brace behind the seat is separate from the diagonal brace (runs from behind my head to the passenger side down section of the main hoop), but is connected to the brace with a piece of pipe for support and rigidity. The horizantal tube is also the correct place to mount the harnesses. We elected to mount the front cross tube above the steering wheel as I am quite long legged and a CRX has a feature that makes installing it below a major chore. This tube can be where you want it so long as it connects the 2 down tubes. There is another one running just below the roof as a connection between the 2 sides as well. We elected to add the 2 forward lower tubes under the dash. Now for the rear bracing. The KIRK cage uses the pans directly behind the wheelwell as a mounting point on each side. The way the cage is welded makes this a very strong way of doing it and does not impinge on the bend in the top of the main tube. If you are concerned about shock tower flex there are several other ways of dealing with that issue.
You mention that you intend to drive the car for a while. Mine remains street legal for now even with the NASCAR style bars. It is harder to get in and out, but manageable. The bars that KIRK provides do not go into the door, rather they stop just inside the metal inner frame. This worked well for me and allowed me to retain the windows (for now) and have replacement door panels made (looks a bit like a street rod) while keeping the upper part.
BTW: My cage was fabricated using 1.75 x .120 DOM as the difference in diameters is minimal from an installation point of view. We also installed an M&R window net per the rules and it does not interfere with anything.
Hope this give you some help. If you are still concerned, you should definitely contact Sven Pruett after the Runoffs next week. Kirk Racing Products is located in Mt. Olive, AL.

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'89 CRX Si-SCCA ITA
'96 Civic HB Just cruising daily
'99 Prelude=a sweet song in motion

[This message has been edited by jc836 (edited September 16, 2002).]

09-16-2002, 02:43 PM
suggest you contact B90278, AKA Bernardo Martinez, he runs a CRX and broke the track record at sears point the first time there. whatever he has it works well.

racer-025
09-16-2002, 03:05 PM
Originally posted by jc836:
Mounting points on the KIRK have the forward down tubes butting up against the front edge of the dashboard


I build my cages this way as well. Arguably, IMO this the best location for the front uprights in an IT cage. Since we are not allowed to attach the cage to the a-pillers, I believe that installing the down tubes in front of the dash, creates too much bend in the tube, thus being the weak point in a roll-over. Some cage builders reinforce this area.

Domino
09-16-2002, 03:57 PM
Originally posted by racer-025:
I build my cages this way as well. Arguably, IMO this the best location for the front uprights in an IT cage. Since we are not allowed to attach the cage to the a-pillers, I believe that installing the down tubes in front of the dash, creates too much bend in the tube, thus being the weak point in a roll-over. Some cage builders reinforce this area.



Actually, the angle (bend) of the down-tube would not change since it is following the same imaginary parallel line of the same fixed plane (the windshield). The bend would just be further down the tube. The two front down-tubes will be connected, horizontally, by an intrusion bar that runs the length of the dash (where the windshield meets the dash). I thought that it would be best to keep the area of impact (the area that meets the roll bar in a crash) as far away from the driver as possible, within the limits of roll cage structural integrity of course. I also see the added benefit being the fact that the mounting points would be 1' more forward then mounting it staight down from the dash, effectively "tying" more the car together, thereby increasing structural/torsional rigidity (by whatever small percentage). Again, this is just my analysis.

jc836
09-16-2002, 05:28 PM
Interesting way of looking at it and it does apply to cars built for GT category racing. Unfortunately the way the IT rules read, I suspect you would be hard pressed as to how to keep the dash reasonably stock and have the bar fit at the same time. Also, any bends in it change its structural function.

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'89 CRX Si-SCCA ITA
'96 Civic HB Just cruising daily
'99 Prelude=a sweet song in motion

Domino
09-16-2002, 06:12 PM
Originally posted by jc836:
Interesting way of looking at it and it does apply to cars built for GT category racing. Unfortunately the way the IT rules read, I suspect you would be hard pressed as to how to keep the dash reasonably stock and have the bar fit at the same time. Also, any bends in it change its structural function.



It would just be a matter of notching the back of the dash closest to the windshield and underneath the A/C vents. I have the dash out now and worked it out. It really wouldn't be any worse then people who put the down-tube right through the vent...which I have seen a lot. Of course this design wouldn't work for all cars...maybe just the small CRXs http://Forums.ImprovedTouring.com/it/biggrin.gif

Richy Gonzalez
09-17-2002, 08:28 AM
Domino,
FYI, click on the link below for pictures of the cage in my crx. The only tube that I didn't put in is where the passenger goes. I still like to take passengers in the crx on track days.

ITA CRX (http://groups.msn.com/TheGonzalezFamilyRichySheilaandNyah/projectitacrx.msnw)

------------------
Richy Gonzalez
Gonzalez Brothers Racing
#21 ITA CRX (http://groups.msn.com/TheGonzalezFamilyRichySheilaandNyah)

Tom Blaney
09-17-2002, 08:39 AM
Quite a cage job. I'm curious what the car weighs with all the tube. It is welded very well, but there certainly are a lot of tubes...

Domino
09-17-2002, 09:37 AM
Originally posted by Richy Gonzalez:
Domino,
FYI, click on the link below for pictures of the cage in my crx. The only tube that I didn't put in is where the passenger goes. I still like to take passengers in the crx on track days.

ITA CRX (http://groups.msn.com/TheGonzalezFamilyRichySheilaandNyah/projectitacrx.msnw)



Two things will be left on Earth after a nuclear war...roaches and Richy's CRX http://Forums.ImprovedTouring.com/it/cool.gif I have a couple of questions.
1. It looks like you removed the ugly, rusted center piece that held the radio and A/C and the glove box. Since we have to keep the dash stock, this is legal?
2. How is the seat attached to the rear horizontal bar? Did you have to make holes in the seat and bolt a plate to it?
3. Are the plastic door kick panels necessary?

I swear I have so many questions (outside of the GCR language) there is the potential of me to annoy everyone on this page.

09-17-2002, 10:47 AM
allthough its probly necessary the tube that bends around the back of the seat,I would find another way, theres no side impact strenght at rib height.

Domino
09-17-2002, 12:42 PM
I finally found pictures of what I was talking about regarding the placment of the front down-tubes. Look at this work by Krause and England in NC. Very sweet looking tubes BTW.

Neon - http://www.krauseandengland.com/KE-project...%20downtube.JPG (http://www.krauseandengland.com/KE-projects/projects-1/Ugo%20Neon%20downtube.JPG)
M3 - http://www.krauseandengland.com/KE-project...ects-3/ugo1.jpg (http://www.krauseandengland.com/KE-projects/projects-3/ugo1.jpg)

Fleetcare
09-17-2002, 03:13 PM
I dont mean to bash Richy or get anyone in trouble by asking this... so here goes.

Is the triangulation allowed in the passanger door and on the rear hatch area ?

I would love to have some sort of bar system on the passanger side door but I was under the impression that it is not allowed..

ANd where do you guys buy your metal materials from ?


Thanks

[This message has been edited by Fleetcare (edited September 17, 2002).]

jc836
09-17-2002, 03:14 PM
To answer several of your questions:
1. The housing for the AC/heater control is part of the chassis (my interpretation)and thus must stay along with the heavy piece that fits in there vertically. This created a real problem in my case as to where to locate the horizontal bar-yes you can cut this thing to get the bar in, but is that the best solution.
2. The rule on the interior door skins is actually very simple IMO. You need something to cover the top such that the window, if still installed can work. THe only exception is where the NASCAR bars penetrate the door cavity-then you need something to protect the sharp metal edge (windlass-welting works great for this). In our case the stock inner UPPER panels are on the doors and the bottoms conform to the rule which says you are to cover the bottom of the passenger and dirvers doors. The rules makers say we are to use .060" aluminum sheet for a covering.
3. The seat must be attached to the tube with a horizontal member bolted to the seatback ONLY if it is made of tubing or metal (Kirkey for example). Those of us with FIA Fibreglas or Kevlar seats are exempt. The rules state that compliance with this will rest with the competitor and the proof-LABEL-shall be permanently attached and visible at all times at tech.

------------------
'89 CRX Si-SCCA ITA
'96 Civic HB Just cruising daily
'99 Prelude=a sweet song in motion

Domino
09-17-2002, 03:32 PM
Originally posted by jc836:
To answer several of your questions:
1. The housing for the AC/heater control is part of the chassis (my interpretation)and thus must stay along with the heavy piece that fits in there vertically. This created a real problem in my case as to where to locate the horizontal bar-yes you can cut this thing to get the bar in, but is that the best solution.
2. The rule on the interior door skins is actually very simple IMO. You need something to cover the top such that the window, if still installed can work. THe only exception is where the NASCAR bars penetrate the door cavity-then you need something to protect the sharp metal edge (windlass-welting works great for this). In our case the stock inner UPPER panels are on the doors and the bottoms conform to the rule which says you are to cover the bottom of the passenger and dirvers doors. The rules makers say we are to use .060" aluminum sheet for a covering.
3. The seat must be attached to the tube with a horizontal member bolted to the seatback ONLY if it is made of tubing or metal (Kirkey for example). Those of us with FIA Fibreglas or Kevlar seats are exempt. The rules state that compliance with this will rest with the competitor and the proof-LABEL-shall be permanently attached and visible at all times at tech.




1. From Richy's picture it shows that he cut this out. The only thing left is the vertical bar. The piece that holds the A/C etc is part of the dash but has brackets so it can be attached to the floor. I would think that we could remove this because it serves no purpose and it is sharp as crap (cut my hands all over trying to remove remove the carpet.)
2. I should have rephrased this question. I was refering to the long plastic panels that hold the carpet onto the door edge. No carpet = no need for panels.
3. My question resulted from what I saw in Richy's car...a Cobra Monaco seat. Which is a FIA approved tube frame seat...same as I was planning to purchase.

Fleetcare
09-17-2002, 05:53 PM
Originally posted by jc836:
To answer several of your questions:
1. The housing for the AC/heater control is part of the chassis (my interpretation)and thus must stay along with the heavy piece that fits in there vertically. This created a real problem in my case as to where to locate the horizontal bar-yes you can cut this thing to get the bar in, but is that the best solution.



Im slightly confused. I cannot see how the heater control panel can constitute a part of the chassis any more then a glove box. Please explain/defend

jc836
09-17-2002, 06:07 PM
On the seat question, I am of the understanding that only the composite/fiberglas seats qualify for the exemption. Please read Rule 18.3.5 for why I think as I do. BTW: I spoke with Kirkey and did not get very far with them on this.
The car may be gutted with specific exceptions. The door sills and other plastic pieces may be removed entirely. We removed every panel except the dash and door skins. What we did do-as a protective measure and appearance item was to install windlass/welting around the door frame area over the pinch welds. I also took the liberty to replace the plastic channels used for the wiring harness with split sleeving.
Now to the AC/Stereo console bracket. Removing the carpet is done one of 2 ways. Either cut it from the firewall out to the offending area or lift the brackets up-which is what was done on my car. I will assume that one could interpret the rule more loosely than I did and remove most of it except the part that actually retains the heater/AC control unit-which must be functional even if you cannot get to it (odd, but that is one opinion I have been given). I also raise the question of the usability of this space for a gauge/switch cluster as that is where mine is going. We are about to fabricate an aluminum panel that will wrap around the bracket and the driver side of this will be suitably padded. Once the car returns from the Fab shop I will have more pictures of it available.

------------------
'89 CRX Si-SCCA ITA
'96 Civic HB Just cruising daily
'99 Prelude=a sweet song in motion

Richy Gonzalez
09-18-2002, 11:53 PM
Sorry guys for not being be able to check this post for a while but here it goes.

First - Thanks for compliments on the cage. While I don't have the best components in my car, I do have the best cage money can buy. Well, that short of a Audi WC car http://Forums.ImprovedTouring.com/it/smile.gif

Seat - My seat has an FIA rating therefore it doesn't require a back brace.

Triangular tubes - They do not have a separate mounting location and are welded within other tubes. GCR says you can have as many tubes as you want as long as you only have 8 mounting sections to the body.

Dash part/heater control - They have been removed because of my "knee bar". It runs right where it gets mounted. Now, I could go through the trouble of cutting the factory dash piece to fit it back in but I don't think is necessary. If I didn't have a knee bar, then I would argue of removing it for no reasons.

Door panels - I can't remember if they the rule which states you must leave them in is still in affect. I've seen a lot of IT cars with and without them and without an aluminum panel either. While I have my panels in my shed, they are not in the car. If this is a problem, I would be more than happy to put them back in.

PS: Did I mention that I'm 6'2'', 245lbs in a CRX. And yes, I'm not anything close to minimum weight http://Forums.ImprovedTouring.com/it/biggrin.gif

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Richy Gonzalez
Gonzalez Brothers Racing
#21 ITA CRX (http://groups.msn.com/TheGonzalezFamilyRichySheilaandNyah)

Domino
09-20-2002, 09:28 AM
Originally posted by Richy Gonzalez:
Sorry guys for not being be able to check this post for a while but here it goes.

First - Thanks for compliments on the cage. While I don't have the best components in my car, I do have the best cage money can buy. Well, that short of a Audi WC car http://Forums.ImprovedTouring.com/it/smile.gif

Seat - My seat has an FIA rating therefore it doesn't require a back brace.

Triangular tubes - They do not have a separate mounting location and are welded within other tubes. GCR says you can have as many tubes as you want as long as you only have 8 mounting sections to the body.

Dash part/heater control - They have been removed because of my "knee bar". It runs right where it gets mounted. Now, I could go through the trouble of cutting the factory dash piece to fit it back in but I don't think is necessary. If I didn't have a knee bar, then I would argue of removing it for no reasons.

Door panels - I can't remember if they the rule which states you must leave them in is still in affect. I've seen a lot of IT cars with and without them and without an aluminum panel either. While I have my panels in my shed, they are not in the car. If this is a problem, I would be more than happy to put them back in.

PS: Did I mention that I'm 6'2'', 245lbs in a CRX. And yes, I'm not anything close to minimum weight http://Forums.ImprovedTouring.com/it/biggrin.gif



Do the tech people frown upon "U" bending of the horizontal bar behind the seat? In the case of a tall driver or someone who likes to sit a little further back the CRX allows no room to push the entire main hoop back a little. The only alternative is to bend the driver-side portion of the horizontal bar to accomodate the seat and harness. Although I don't think the rule book says you can't (still waiting for my GCR) do they give you a hard time?

Richy Gonzalez
09-20-2002, 10:21 PM
Domino,
While the GCR specifies the minumum set of require bars and attachment points, it doesn't state that the bar behind the driver within the main hoop can't be bent. Lots of cars are done this way. Also, no tech inspector has ever had a problem with my cage or any other cage down here in SEDIV which is built similarly. In the other hand at my driver's school, I had nothing but compliments on the cage. Hum, I wonder if it's because it is painted lime green:P ... all I kept on hearing was "Oh yeah, the car with the green cage. Nice cage!"

------------------
Richy Gonzalez
Gonzalez Brothers Racing
#21 ITA CRX (http://groups.msn.com/TheGonzalezFamilyRichySheilaandNyah)

jc836
09-21-2002, 06:49 AM
The rules permit bends in the tubing that meet the standards for bend radius. My KIRK cage has the horizontal bar mounted with a bend on each end. The seat and cage are as far back on the floor as is possible and yet allow the feet of tubing to be welded to the floor fully. I suspect that there might be an issue with using NHRA style bars- so my suggetion is to have the horizontal mounted so that it is a solid piece going from end to end with bends on the ends meeting accepted standards. This will also give you a location for the required harness assembly and the height of the bar will be set based on the seat and harness location relative to the driver. The GCR has a good view of this as does the SImpson catalog.