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rollcage help..

Old Mar 13, 2003 | 07:10 PM
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rollcage help..

Where can I find I good source for rollcages for my 91 FC? Like perhaps a bolt in kit?
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Old Mar 13, 2003 | 09:50 PM
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From: sca
auto power. pretty good price and quality
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Old Mar 13, 2003 | 10:04 PM
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KirkRacing built the cage in my car. The cool part is the owner of the business road races an FC.

http://www.kirkracing.com/
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Old Mar 14, 2003 | 06:03 AM
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Do you want a roll bar or a cage?

I'd stay away from bolt in cages, havent' seen a Kirk mounted, but the Autopower is definitely too close to your head unless you're a pretty short guy, plus the door bars are a little low for my tastes.

PaulC
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Old Mar 14, 2003 | 12:49 PM
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I have the Kirk, very reasonable price, DOM tubing only, tell him what you have, ie full interior, stripped etc. he will build the cage to suit your situation. Very knowledgable on FCs particularly. Carl Byck
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Old Mar 14, 2003 | 10:26 PM
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I have seen bolt in kirk cages, they are like the autopowers. I would personaly stay away from them.
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Old Mar 15, 2003 | 12:40 AM
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My Kirk is a weld in with an Xbrace in the rear, door bars, dash bar etc. I think any bolt in will be a compromise, but if you want to maintain a full interior it is an easier way to go. In addition MRimport, have you seen a better bolt in that you can share with the group?
Carl Byck
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Old Mar 16, 2003 | 10:31 PM
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Cool thanks alot guys..and yeah im looking for a full cage. Whats wrong with bolt in cages?
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Old Mar 18, 2003 | 03:09 AM
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Originally posted by GeTCrAzYKiD
Cool thanks alot guys..and yeah im looking for a full cage. Whats wrong with bolt in cages?

NOT too save. usually the tubes always close. because they build from full interior. and the base might snap during roll over. and it doesnt give to many reinforce at chassic. If u plant to do some TRACK DAY or SOLO2 the roll bar is more than enought
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Old Mar 18, 2003 | 09:38 AM
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The Kirk cage I have is welded and was custom made for my car. I am fortunate enough to live just a few miles from his shop and was able to leave the car with him for a few days.

His bolt in cages are very safe. He has an FC sitting behind his shop that he personally rolled at Robeling Road while using one of his bolt in cages. The car is trashed and is now used for parts. The roll cage did its job and was not bent in any way.

Bolt in cages became popular when SCCA's Showroom Stock and Improved Tourign classes REQUIRED a bolt in cage. Since then the rules have been changed to allow welded cages in thoses classes but they are still regularly used.
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Old Mar 18, 2003 | 11:36 AM
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Carmon,

Where's the main hoop bolt to?

If it's the thin sheet metal behind the drivers seat, you might feel safe, but there's no way in hell I would. I've heard and read about too many punch throughs where the cage goes through the floor on a roll over to feel safe with that.

PaulC
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Old Mar 18, 2003 | 02:39 PM
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Geez, I wish you guys would quit bagging on bolt in cages. I'm sure most, if not all of you have never seen one fail and have no practical experience with one. Quit spreading bs assumptions or have heards. I have been t-boned and wrecked headon into a wall @ 40mph or so with a bolt in autopower cage. Car was trashed in both cases. In both cases my head was not hurt since there was padding (didn't even hit my head from the frontal impact). Fact of the matter is that when I was t-boned, I probably would have hit my head on something harder inside the car if the cage was not there. Not to mention the door bar saving my ***. Just sold the same cage to GNX7 since it is in good shape still (minus one door bar) and I am going with a full welded cage now. Sure a bolt-in is a compromise (of course a weld in is far superior) but it is still better than nothing. I'm sure boltins have punched though where they mount on extreme occasions but imagine if they were not there at all. Besides they are WAY cheaper and not everyone can afford the big bucks (2k-4k vs. $600), plus you can keep the entire interior which is a real bonus with a street car. Both a welded and bolt in compromises space. Of course a weld in is slightly less, but unless you are really fat or really tall, a bolt in is just fine. I am 5'10" @ 160 lbs.

Last edited by RX-Heven; Mar 18, 2003 at 02:50 PM.
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Old Mar 18, 2003 | 04:35 PM
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Bolt-ins can cause punch through problems because the mounting pads are generally too small and any load applied is concentrated. Not good.

$2k-$4k for a custom cage? HA! Someone is getting bent over. I got my custom cage for around $1000 and I would put it up against any cage costing twice that amount in terms of strength/rigidity.

Judge for yourself.

http://home.mindspring.com/~twire/_wsn/page2.html
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Old Mar 18, 2003 | 05:04 PM
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Dave,

Great, I'm very happy that your two bolt-in cages saved you. Unfortunately, I've read about several deaths and near misses from cage punch throughs that leave me unwilling to recommend a bolt-in cage. Have I ever had or seen a failure yet? Thankfully no.

You want to argue the point in this thread or any future threads, please do so, but I'm not going to stop strongly recommending against bolt in cages just because you had a good experience. I've read of plenty of others who have been fine, even after rollovers. Obviously if they failed a great deal, no one would buy them.

Regards,

PaulC
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Old Mar 19, 2003 | 03:10 AM
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Originally posted by TeamWireRacing
Bolt-ins can cause punch through problems because the mounting pads are generally too small and any load applied is concentrated. Not good.

$2k-$4k for a custom cage? HA! Someone is getting bent over. I got my custom cage for around $1000 and I would put it up against any cage costing twice that amount in terms of strength/rigidity.

Judge for yourself.

http://home.mindspring.com/~twire/_wsn/page2.html
Welding on a larger plate to distibute the load at the mounting points, either onto the car or the bolt in cage mount solves that problem easily. I threw out high estimates to emphasize my point. Anyways, thats about the going rate for a reputable race shop that will TIG one together in a few days. Sounds like you got a smoking deal, like a 'hook up'. I've seen pix of your cage before, very nice job. No worries there, for sure. It looks like $1000 worth of tubing alone
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Old Mar 19, 2003 | 10:28 AM
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If anyone is paying over 2K for a welded cage(in an IT type car) they are over paying. DOM tubing for an 8 point cage costs around $300 and labor from a reputable fabrication shop should not be over $1700. I personally have seen an Autopower bolt in cage rip through the floor on an IT datsun 510 in a multi flip rollover after catching a wheel in the dirt. driver was un hurt but cage, still intack, was pushed/pulled through the floor. I have also seen poorly built welded cages do similair things, front leg was ripped from the rocker panel in a t-bone crash. If the bolt in cage gives you adequate room for your head and is installed correctly it should do what it is designed for, protecting the driver in the event of a roll over. they do little to strengthen the chassis or protect the driver from head on or t-bone type crashes. the standard 8 point rollcage does a little better job if installed correctly. if the cage is welded to the thin sheet metal of the floor it is really no better than the bolted cage. it needs to be attached to the structural parts of the chassis. unibody cars this means the rocker area, rear suspension mounting areas, and the firewall. large base plates and gussets will help. making sure the driver is well away from the cage is also possible, as well as proper window net mounts, seat mounts, and driver restraint mounts. I tell people all the time who want to get into racing. spend the bulk of your initial budget on safety gear. all the performance modifications can come later. make sure you are safe and protected. in my limited number of years I have been involved in two fires(one fuel), two very bad high speed collisions(resulting in one write off), and thankfully no roll overs. Thankfully I have had nothing worse than a few bruises. if you want to do any wheel to wheel racing then the minimum entry is all the required safety equipment, and the there is no way to get around the fact that racing is terribly expensive at any level.
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Old Mar 20, 2003 | 04:07 AM
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Speaking of Roll Cages
Has anyone had experience with the Jegs Roll Cage available for the FC Rx7?
These cages are similar in a way to the Autopower cages but rather then a bolt in cage, these cages require the bars to be welded together.

I'm currently interested in ordering the 10 point availble for my Rx7. Would this cage be SCCA approved?


http://www.jegs.com/cgi-bin/ncommerc...00&prmenbr=361
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Old Mar 20, 2003 | 09:03 AM
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Originally posted by Silkworm
Carmon,

Where's the main hoop bolt to?

If it's the thin sheet metal behind the drivers seat, you might feel safe, but there's no way in hell I would. I've heard and read about too many punch throughs where the cage goes through the floor on a roll over to feel safe with that.

PaulC
I have not installed a Kirk Bolt in cage so I can't say for sure exaclty how the main hoop is mounted. But I have installed a Kirk Solo I Roll Bar. The main hoop of it mounted to the sheet metal behind the driver/passenger seat (as close as possible to the outside and as far back as possible). Each point had a two ~6"x~6" plate (1/4" thick?) that sandwitched the floor pan. They were bolted together with 4 large bolts.

On the link below browse through the "ProjectPartsTrader" photos and look for one called. "Kirk Racing Bar (right lower)"

http://photos.yahoo.com/thepartstrader
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Old Mar 20, 2003 | 09:30 AM
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Has anyone had experience with the Jegs Roll Cage available for the FC Rx7?
I'm currently interested in ordering the 10 point availble for my Rx7. Would this cage be SCCA approved?
if it is an IT car then it would not be legal. IT rules limit the cage to 8 mount points. before you do any modifications though I would suggest you get the rulebook for the class you are going to run. the Jeg's kit is likely designed for drag racing and may no be made from the correct diameter and wall thickness material to qualify for the SCCA. the SCCA as well as other sanctioning groups have changed some of the requirements for roll cages so check the current rulebook before doing any work.
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Old Mar 20, 2003 | 09:38 AM
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Each point had a two ~6"x~6" plate (1/4" thick?) that sandwitched the floor pan. They were bolted together with 4 large bolts.
unless the plate is very large(normally it is 4"x6" or 4"x5") you are relying on a 18ga piece of sheet metal sandwiched between two thicker plates. the floor is still the load bearing part. the sheet metal in these cars is very thin and unless you can connect the cage to the main load bearing part of the chassis it is not as strong as it could be. in most roll over situations it will be fine, but if the car barrel rolls or hits hard on the roof there is potential for problems.
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Old Mar 20, 2003 | 09:44 AM
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Looking at those pictures of the Kirk bar, I would not buy it. The mounting plates are not in the ideal places. The floor mount of the main hoop is probably one of the areas that it could punch through. And mounting the rear braces to the top of the tire well is almost pointless, esspecially in terms of chassis stiffness. I would think the main hoop should be mounted on the top outside edge of the cross brace that goes behind the seat, and the rear braces should go to the top of the shock towers.
But that's just my opinion.
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Old Mar 20, 2003 | 05:03 PM
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Originally posted by Travis R
Looking at those pictures of the Kirk bar, I would not buy it. The mounting plates are not in the ideal places. The floor mount of the main hoop is probably one of the areas that it could punch through. And mounting the rear braces to the top of the tire well is almost pointless, esspecially in terms of chassis stiffness. I would think the main hoop should be mounted on the top outside edge of the cross brace that goes behind the seat, and the rear braces should go to the top of the shock towers.
But that's just my opinion.
I think the SCCA Solo I bar rule dictated the design and attachment of the bar I had installed. I agree there are much better ways of mounting it. And all it takes is asking for them to build one that attaches where you want it to. I only used that 4pt. bar for around 6 months before KirkRacing welded in a custom 6pt cage (nascar door bars, dash bar, rear X bar, etc.).

I agree that a welded cage is stronger and safer but I would not call a bolt in cage unsafe. It has to be better than nothing at all.
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Old Mar 21, 2003 | 08:01 AM
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Originally posted by ThePartsTrader
I agree that a welded cage is stronger and safer but I would not call a bolt in cage unsafe. It has to be better than nothing at all.
I agree.
There is actually an extenuating circumstance with the miatas. There is a double hump "style" bar that has raised some questions about this very topic. Some people believe that they have caused more injuries because they fold over onto the driver during a roll-over. They don't have any forward or rear bracing.
Be safe out there.
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Old Mar 21, 2003 | 10:01 PM
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gee, from reading your posts, im not sure what i should even go with anymore. And, ontop of that, i still have a full interior and i wish the keep it.
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Old Mar 21, 2003 | 10:23 PM
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The Kirk weld in cage main hoop mounts on the outside edge, just forward of the storage compartments. the x-brace runs from the sheet metal just behind the rear wheel wells to the main hoop. The forward left and right bars run from the main hoop along the roof, down the A pilar, and are welded to a plate on the floor, and a second plate welded to the side of the footwell. Anyone who doubts the Kirk cage should talk to the owner who has been upsidedown in his own FC, and walked away. The cage comes standard with DOM tubing, a dash bar, rear X brace, and two door bars per side. Not a bad deal for less than 700.00. Hope I'm right because that's what's in my car Carl
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