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Old Mar 20, 2005 | 05:09 PM
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Roll cage

Since I will be porting my engine using Judge Ito's template, and putting a T61 turbo on my car I am thinking about a roll cage. This is a daily car that I will be taking to the track. The one im looking at right now is http://www.ioportracing.com/Merchant...egory_Code=MDI

I want to weld that in, but is there a special procedure your supposed to follow? for example is the car supposed to be on the wheels or is it supposed to be on jack stands? Someone was also saying something about pushing a push piston and pushing the legs apart when installing it so its stiffer.
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Old Mar 20, 2005 | 07:11 PM
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Nothing against autopower products but you can do better by finding someone that does custom cages in your area. They will attach the cage to better places on the chassis then the autopower bolt in cage(which probably goes to the floor). If you can weld yourself see if you can find someone to bend up the tubes for you, but remember its your safety on the line. Most of the time building a cage is spent fitting the joints before welding. Decide if you are keeping the headliner and all that stuff before the build for fit reasons. If you don't have rules or cost is an issue start with a custom 4 pt roll bar and add the front later. Tell the cage builder your future plans(add on) because there may be a slight difference in how the main hoop would be made (for welding new stuff to it later). Check with the SCCA in your area for cage guys. It's good to use their rules to build by just in case you get the itch later. I heard a long time ago that they have the best safety record in the world because of these rules, don't know if that's still true.

The car should be on the ground, level, with the load going through the normal suspension points when you weld. You would be suprised how doors won't close right if the cage is welded in with the chassis "jacked" a little. Don't ask how I know this

Last edited by jgrewe; Mar 20, 2005 at 07:19 PM.
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Old Mar 20, 2005 | 10:36 PM
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I really dont feel like going through the hassle of designing my own cage. My dad is a welder, thats what he does for a living so thats who will put it in for me. We got a good MIG welder at home that we use. The reason I want to go with the autopower cage is because its certified for basically all the racing organizations including SCCA and the NHRA. Also I know a guy who bought an autopower cage for his car and he said it works very well. I dont really see any problems in the design, and he said he can jack up the car, take a wheel off, jack it back down and the car will stay up on 3 wheels. Thats pretty stiff.

Can you point out whats wrong with the autopower cage because I dont think I can do a better job myself, and I dont want to pay some company a lot of $$ to have one custom made.
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Old Mar 20, 2005 | 11:09 PM
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In general nothing wrong with them, its just the bolt in cages usually attach to the floor to bolt through and double up with a plate on the underside. The metal in the floor isn't that thick. A well designed bolt in cage itself can be pretty strong, it's the floor that is the weak link. The other issue is the bolt/sleeve clearances. A little movement at each joint adds up. Does autopower sell a weld it yourself kit? That could be something. Hell I could bend up something to fit a parts hulk that I have laying around, let me know if that interests you. A basic cage only has 8-12 bends in it.

If you go with the autopower kit and bolt it to the floor, round off the corners of the base plates at about a 1/2" radius. It will help keep them from ripping through the floor if you happen to "test" the cage.
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Old Mar 21, 2005 | 12:25 AM
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I'd look at the Kirk cage, I have one in my FC, and he will custom it to your exact wants for a very small upcharge. All rear supports, and the main hoop weld to the frame, not the floor. Carl
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Old Mar 21, 2005 | 03:16 AM
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It seems like I end up talking about this subject a lot, since I have had both a street car and a race car with full cages.

Every time you get into a race car, you pretty much have full protective gear on including an up to date helmet and racing belts cinched tight. The same can not be said for street cars. Every time I drove the street car with the cage I thought to myself that the cage was more likely to cripple or kill me than any other single thing inside the car. It may keep the roof from collapsing in a roll over, but in even a relatively minor fender-bender you might slam your head into a nice DOM steel tube which has a pretty fair chance of killing you! I wouldn't really consider putting a cage in any car that I didn't intend to wear a helmet and five point harness in at all times. I properly located, constructed, and padded roll bar might be OK depending on the set-up, but not a cage. Stock belt allow a lot of movement which would be unacceptable. Even SFI race belt start to show deterioration and stretch in a very few years requiring mandatory replacement. FIA certified belt stretch the least, but still are a gamble without a helmet. And all of that doesn't take into consideration the stock energy absorbing crumple zones that are built into modern cars.

So - it sounds cool and protective in theory, but I worried about banging my head on the door or windshield bar every time I drove that car, and eventually took it out and felt MUCH safer. Just my 2 cents worth of experience.
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Old Mar 21, 2005 | 11:24 AM
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So should I just go with a roll bar then, since I will be driving this on the street. Whats a good roll bar to get? CP racing sells one but I dont know how good those are.

Any suggestions?

BTW, even if the cage is made to be bolted in. I would weld it in instead at those same points.

Last edited by Net Seven; Mar 21, 2005 at 11:30 AM.
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Old Mar 21, 2005 | 11:27 AM
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Here is the CP racing roll cage. I think if I put some padding on it, it should be fine for the head area.

CP racing custom roll cage 1 3/4 tube with an .095 wall, mandrel bends, can be welded or bolted into vehicle,requires NO ASSEMBLY of cage, all prewelded just painting required. Easily installed by removing seats and slipping into place. Can be used with or without interior, perfect for road course, drag, show cars or drifting. Seats can still be moved back all the away without hitting cross brace, allows for harness mounting(email for price on disassembled cage.)
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Old Mar 21, 2005 | 12:06 PM
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Where's the diagonal?

In short:
If you feel the need to install a bar in your car for racing (either because you are going fast on the drag strip or are doing track/lapping days) don't cheap out and get the right one from the get-go. Been there and lost money and time on a poorly designed bolt-in that I was told was legal for Solo-I and wasn't.
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Old Mar 21, 2005 | 12:34 PM
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on this topic, would the CP racing bar or similar be legal for solo 2? I have the back half of a cage basically main hoop aft and skimming rules the say there must be 2 braces (fore/aft) of main hoop. I would like to put it in just don't wanna hassle with SCCA tech. Oh I would be in CSP. Running locally.

/hijack

Last edited by BMS2004; Mar 21, 2005 at 12:45 PM.
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Old Mar 21, 2005 | 12:51 PM
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I have the AutoPower cage and I find it acceptable. Many of the custom cages are built to go through the dash vents and mount to the floor much closer to the firewall than the AutoPower cage. That's better but it requires modifying the stuff inside the dash.

The door bars are a little on the low side but that makes it easier for entry and exit on the street.

You have a fair amount of leeway in positioning the bars. Try to make sure the bars line up with the drivers-eye view of the A-pillars.

I find the rear portion of the AutoPower leaves plenty of room for carrying tires in the hatch.

At first I could jack up one wheel and the doors would open and close as easily as on the ground. After a few years of racing, the chassis will get flexible no matter what you do (probably even if you weld some upper tabs to the cage - a no-no for IT in the SCCA).

ed
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Old Mar 21, 2005 | 04:37 PM
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I called kirk racing and the lady recommended the 4 point roll bar for me. She said its over the standards of solo 2. If NHRA needs 6 point she said all I have to do is weld on 2 bars off the loop towards the firewall. It's $350 for that roll bar, sounds fair to me.
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Old Mar 21, 2005 | 05:47 PM
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Originally Posted by Net Seven
It's $350 for that roll bar, sounds fair to me.
Don't forget to add shipping in with that

Isn't cagedruss up your way? If I were you, I'd shoot him a PM or email. If you haven't already, check out the "show us your cages" thread for examples of his work.

Custom cages are just that... custom fit to your car. If you don't want the downbars through the dash, tell the builder and they won't go through the dash. Want a tighter fit than the CP bar (which wouldn't be too hard LOL), no problem.

Do your homework and get the most cage for your money. Some of the mail order companies use thicker tubing than they really need to and few of their bars fit as tightly as they could. Kirk cages are very nicely done for their price, no doubt about it, but they're not the only option out there (especially when there are plenty of RX7 nuts on this board that can bend you up a great bar/cage).
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Old Mar 21, 2005 | 07:08 PM
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I would check to see if CP Racing offers more than one "custom" roll bar! It looks like that one will also fit Omni, Escort, Miata, Chevelle, Yugo, CRX, Beetle(new&old), Grand Am and Turner Mk 3. Did I miss any? Seriously, you can find someone to bend up something for YOUR application for the money you are looking at spending. Don't worry about designing it let the cage guy worry about that. And it will look like it was meant for your car and function better.

If its mainly for SOLO II, I would try to tie into the shoulder belt bolt holes with just a rollbar. A lot of metal in that area. (Don't think it's legal in IT though)
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Old Mar 21, 2005 | 09:32 PM
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Regarding bumping your head on the cage in a street accident... a well padded cage is probably better for your head than the stock interior, which is cheesy plastic backed up with the steel frame of the car. Of course, the stock interior is that much further away from your head, so you might never hit it in the first place.

Last edited by Gene; Mar 21, 2005 at 09:36 PM.
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Old Mar 21, 2005 | 11:05 PM
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Originally Posted by jgrewe
If its mainly for SOLO II, I would try to tie into the shoulder belt bolt holes with just a rollbar. A lot of metal in that area. (Don't think it's legal in IT though)
Nope, not legal in IT.

Then again, if you're running the car in club racing, you really should consider making it a full-time racecar, rather than dual-purpose. In wheel-to-wheel racing, something's likely to happen eventually, and it sucks when you drove your racecar to the track and can't drive it home.
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