ERW or DOM
 

JUST remember that a bolt in cage (autopower/kirk) is bolted to 22 gage cold roll steel with a 6" square pad. Thats what should be outlawed. Not ERW!!! There no way the ERW cage could be weaker than the floor board of a uni-body car. The cage would push through the floor board LONG before the tubing failed. You know it and I know it.

Yeah, I totally agree with that Dick. I saw a driver die at Phoenix a few years back when his BMW slapped the front stretch wall on the drivers side. Had a bolt in cage and the upper halo allowed his head to reach the wall during impact. Even though the accident was a little freakish, I believe if the cage was properly designed and fitted, driver would have survived.

I personally believe with past experience using ERW, I would never use it unless I stepped up the the next wall thickness. I have done quite a few cars in the past that has ERW for the cage and I am certain the cages will do their job. But, I am a lot more comfortable knowing that all my cages now use a superior tube for construction.

Average cost increase for safety of material is an extra $1.75 per linear ft. That is pretty cheap insurance! We are never going to be able to change it back to the old rules of tubing, nor would I try. I even understand the princible of allowing bolt in cages, but, I do not agree with it. Most kits do not offer enough protection for the speeds of cars they are in.

I took out a very nice fabricated bolt in cage that was in a SPM Porsche and fabb'ed him a new cage. He spent nearly $900 plus shipping for his kit and was only a 6pt with no cross bracing to speak of, and his car was capable of exceeding 160 at will.

Who knows for sure, most of the time racing a crap shoot anyway. You could be cruising around your track with similar cars and cage designs, and then out of no where a 3500lbs 150 mph missle slams in to you and use your car as a bump stop. Big car wins, little car loses.

Either way, show us more pictures of cages you guys have or built. Love seeing them!

DOM or ERW
 

I agree with you 100%!!!! My only reason for answering this posting, was to show that DOM is really ERW to start with, and that SCCA hasn't got a clue how to enforce this rule. Best one the IT.Com web could come up with was to put a bore scope in through the 1/8" inspection hole. LOL. Thanks for your postings. You know your @#$%. DICK (71 and not counting) (better to be a has been, than a never was)

NHRA Division Techs use a hand held sonic tester. They measure a tube from 2 axis'. The meter tells what the wall diameter of each side of the material is, very accurate. That is one reason when somebody buys a drag cage kit, it comes in 1 3/4"x.134". Since ERW has crappy mill specs, I have seen a tube that was .125" rated to have 1 side as little as .113" and the other side .128". Once the tech finds any part of the cage or a tube to fall under the min. 118", the whole cage is illegal. They also do not measure the bends, knowing that the tube stretches during the bending process.

I have used and still use DOM 1 5/8"x.125" for all my Drag cages, supplier gives me a Mill spec sheet showing the lot has a variance of .002-.004". Subtract that from the .125" and I am still above the min. of .118". NHRA also figured out to make the minimum a little under than normal tube size to allow for the variance.

SCCA could adopt the tech procedure, maybe someday they will. That would also find the people that build the main hoop to spec and the rest could be .083" or .065". It is a decent weight savings but could also be a threat to the driver during impact.

I would rather see the sonic test being used than having a bunch of little holes drilled throughout the entire cage or main hoop that allows moisture to enter. It is a simple procedure to test and would pay off in the long run.

Thanks Dick for your involvement!

ERW or DOM
 

Thank you very much. I was a drag racer long before I started going in circles. NHRA never fails to amaze me. They have their @#$% together. I raced Pro-Stock in the old AHRA. Man what a difference between then and now. Much fun back then. Thanks again, DICK.

now this is a racecar
 

I finally remembered to take my camera to the local race shop. This is a new Port City "offset" late model chassis. The car was up on a lift so I got a pic of the bottom side too. I searched their web site but didn't find any info on the material they use. BTW... check out the direction of the cross bar in the main hoop.

a couple more shots
 

The last shot is an older perimeter late model chassis.

8 Point Rollcage Pics.
 

Here are the pics of an 8 point rollcage in an FD.

If you would like to see all the pics click this link...

http://www.rx7s.com/tandrracing/team...Cage/index.htm

Thanks

Anthony

Wanted to show some pics of a car I got to fix last year. Finally found the disc with the pics on them. This car ran in the Bremerton area. It is a Vega wagon drag car. My neighbor purchased the pile of crap with out looking at it well. This can be a good lesson for all, when looking at a race car to purchase, take a friend to look at the car before you buy!

I had to build the car from the ground up.

hey im looking for a list of whe can find places that make cages for second gens. mostly ones i can order online 6pt or 4 pt ect.. thanks

Here are some pics of my 10 point roll cage in a 3rd gen. It's built after the FIA spesifications. There is also a x in the roof too. will take some pics of that too for ya if u want.

http://home.no/jantorep/Bur2/Lakkertbur1.jpg

http://home.no/jantorep/Bur2/Lakkertbur2.jpg

http://home.no/jantorep/Bur2/Lakkertbur3.jpg

http://home.no/jantorep/Bur2/Lakkertbur4.jpg

http://home.no/jantorep/Bur2/Lakkertbur5.jpg

Can't wait to see the finished product, keep posting new pics!!!

Is that true? Swingouts are no longer legal? And since I'm a newb, for clarification purposes, swingouts are the sidebars held in by pins that swing outward, allowing you normal access in and out of the car, right?

Dan, I've seen two cars in person who have 100% full interior, all creature comforts, but have 8 point cages. The first was Anderson's white FD from upper NJ. He's got swingouts. He was at Rotorfest last year. Can't remember if you came?? I didn't get a good look at the layout of the rest of the bars though. The other is Ed Taylor's 3-rotor. It has one of the nicest cages I've ever seen. Ever. Really. The rear car runs along the bins plastic, straight up to the rear strut tower. But it's flush against the plastic (a bit of the plastic had to be cut away so the bar actually sits maybe a 1/4 of the way into the plastic). But it's such a tight nice fit it looks incredible. Then, instead of just going into the strut tower, it turns and runs the length of the strut tower. And IIRC, it runs the length of the strut tower TWICE, once in front, and once in the rear. Long story short, the work on it is amazing. And the swingout side bar comes cleanely very far forward to the ground. I don't recall a bar going right under the roof, and into the dash/pillars...only full car I've seen that in was the Supra that was at PFS. Might be Ray's. I gotta go back to PFS in a week or so, so if Ed's car is still there, I'll see if I can snap some pics of it. Ray told me the guys who did the work are in Baltimore, so you might wanna look 'em up. I also hear Mitch Piper does amazing work too (he's in VA)

I just finished a Supra with a Moly cage with swingouts. I had it chassis certified in Div 6 NHRA. Senior tech said nothing about it at all.

Car is capable of high 8's. See attached pics. Bar follows the letter and intent of the rule. Follow through elbow and shoulder and does not hinder access to any of the door switched and latches.

Best bet is to check with your Division tech to get the straight answer!

i don't understand people's fondness for swingouts. once you get used to it, it's actually still very easy getting in and out with the door brace there. once you get the technique right even tall drivers can slip in and out of the car easily.

$20 says I'll have a LOT of trouble getting in and out, ESP. w/ racing seats in there. I'm bigger than most FD drivers... That, and to be frank, I'm not exactly looking forward to learning a technique. I'd like to be able to leave the swingout bar in the back or at home etc when I'm takin my car for a cruise, and simply not have to deal w/ even greater sports car gymnastics for getting in and out. Some of us (like Scrub and myself) actually want this on a fully equipped street car, not a track-only car.

I agree totally, but some people like to drive their cars on the street and remove the bar all together for their driving experience. It is helpful for the weight challenge drivers to gain entry and exit of a tight cockpit.

I would prefer not to install them for customers and to keep the cage structurally intact!

:rofl: I didn't mean to insinuate that I'm gravitationally challenged lol. I'm 6 foot 220, not much fat (although been too busy to go to the gym in a while...gettin kinda squidgy LOL). I'm referring to sheer size. I have a very wide build...wide shoulders, wide hip. And a tall trunk...not just tall feet. So it makes navigating my way in and out of the car w/o a removable steering wheel (since it doesn't tilt) quite cumbersome. To say the least, I've barely been able to get most customers' cars at other shops I've been to, if at all.

I was curious about that. If the swing out bar is held in place w/ just a pin on the top and bottom, what are those pins made of? Because I'd think those would automatically be the weak points in the cage, which doesn't sit too well w/ me, being that it's the driver side we're talking about. You sit RIGHT THERE. Those pins ever fail/snap in two? Etc?

it's not that the pin is weak, it's just that a true welded cross brace is structurally much stronger than a swingout. the door opening is the weakest part of the chassis so thats where you need the most support. that's why i just prefer a welded door bar, it provides support where you need it most and it ties the cage together nicely to stiffen the chassis. an x-brace is even better, but that's beside the point. you're right though, on a car with alot of street use, swingouts are very convenient. i don't see that 8 sec supra seeing too much street use though.

I checked the NHRA rule book and had the Division Tech over today, Still legal for 8:50 and slower.

Strength of the pin is not a issue for me. What is important in my mind is that a clevis joint is a pivot, not a welded joint. In some instances I could see a clevis or other types of swingout could pivot in during an accident.

Swingouts work, enjoy them.

I guess what I want to hear from you guys is, would you track/race a car w/ a swingout (assuming you're running over 8.5)? Cuz I wanna know if the swingouts are indeed a compromise in your safety, or do you just prefer a welded door bar for peace of mind, but a swingout is def. enough/satisfactory?

So it's been a long time coming since I first started asking you guys for cage advice....but today I finally got the call that it was done and I maneaged to get some pictures of it. Let me know what you guys think

thanks again for all your help in the past!

Hey guys. Here are a few pics of a mates cage that he just got done at City Performance Centre (formerly Rotary Power Australia). Full tig welded, unsure of exact material though. Complies with CAMS (Confederation of Australian Motorsport) regs, so can be used in an Australian racing series. Just wondering what you think of it, and what you think could be improved? Both for safety and rigidity.

And here are a few more. I've only put up the pic's before it was painted so you can see the quality of the welds, etc.

Looks pretty good i think! My only improvements would be getting the bars closer to the roof and pillars, attaching them to the pillars more often, another intrusion bar that runs horizontal between the a and b pillars. I don't think anymore diagonals are needed in the rear section. Would probably add a little more strength and alot more weight. Visibility with this cage is good. It's the same as the GT3's, etc that i work on at work. Good cage :)

Looks good Mate, I would like a little more door bar protection, but all in all it looks good. Builder followed sound principles of keeping all the tube intersected for good compression. Keep up posted after paint and interior.

Russ

Its actually better to keep the front A-pillar bars away from the pillars themselves. With plates attaching them together like you have it creates an "I" beam in an area that needs all the help it can get. You can gain a lot of torsional rigidity in the chassis by strengthening the pillar and cowl area. Add a plate above and below the one you have. One down by the base of the pillar by your dash bar will do the most good.

That' if its class legal..

Yeah, i think maybe another intrusion bar would be good. I'm not into the massive bars you guys in the states use! Pretty ugly! And i'd imagine very heavy!

The interior has already been painted and trim put back in. It's my mates car, not mine! I just asked him if i could put some pics up to see what you guys think, because i'll be getting an almost identical cage fitted to my first gen. Hence why i wanted to know what you'd change and improve!

That was in the plan as well :) I will be adding a bit more bracing to the A-pillars on my cage as long as it stays CAMS approved (the pics are of my mates cage that re just got done). The problem with keeping them away from the pillars is that they start getting a bit close to you!

Not racing in a specific class, just track days for the time being, so anything goes as long as our motorsport body is happy with it!

We don't have specific class "spec" cages. As long as it's CAMS approved for that vehicle, and the vehicle and current mods meet the rules, you can use it.

A Spec Miata just completed:

http://www.izzyscustomcages.com/imag...a/P5200071.JPG
http://www.izzyscustomcages.com/SpecMiata.html

You might also look into "line of sight" issues with A pillar bars. I like to make them asymetrical and line them up with the pillars as I look at them from the drivers seat. Just something to think about as you build yours.

I'd like to keep the cage as "low key" as possible, and keep visibility high so things like this are important. I'll be trying to keep a close eye on what they do with the cage as it's being done. Hopefully it comes out as planned.

You have to understand that the big door bars come from US circle track usage. It's quite easy to spin right in front of a 3400lb car and get hit directly in the door. I believe 2 fore/aft tubes tied together are the minimum any more in SCCA. NASCAR requires more. Most drag racing only requires the one side bar. Cagedruss knows the requirements much better than I as he actually fabs cages. I just like to be knowledgable, go racing and not kill myself.

http://members.shaw.ca/red-man/cage1.jpg

http://members.shaw.ca/red-man/cage2.jpg

http://members.shaw.ca/red-man/cage3.jpg

http://members.shaw.ca/red-man/cage4.jpg

http://members.shaw.ca/red-man/cage5.jpg

I drafted the above cage to give the person helping me an idea of what I was looking for, figured I'd post it here and see if anyone with some experience had some suggestions or input on the overall design.

I'm only building a the rear half as I plan to drive it on the street for the remainder of the summer. This will be built in a '88 RX-7 that I'll be preping for IT/GT and the cage should be able to cross over to CARS (Canadian Association of Rally Sport) rules and regs. I'll be using 1. 3/4 inch DOM mild steel.

the bends in the main roll hoop total more than 180 degrees, so it will have to be built out of the next larger size tubing (according to SCCA rules.)

cage
 

Is this count ? LOL

WAAAIIIITTTT a minute here... this isn't the same Josh that used to run a 66 Dart /6 is it????

Bent bars act as springs... straight bars transfer loads.

Your "dashbar" is a little bit unrealistic.... You'll probably want the downbars to follow the contour of the A pillar instead of just straight down to the floor. I assume that all of the straight bars for the downbar/halo are just representative and not planned to be straight bars welded together?

Remember, you'll be building a ship inside a bottle. Unless you have the dimensions of the bottle when modeling the ship... you're really just playing around. The design of the hoop as well as the downbars and doorbars aren't practical in a real 2nd Gen.

Just my opinion...

Yeah I'd have to break out the CAD program and the measuring tape to be somewhat accurate. This was supposed to be about as good as a rough sketch to give the builder an idea of the overall design I wanted.

What do you think of bringing the front bars through the firewall and to the strut towers? I'd imagine it would be difficult with an FC as the engine bay is a bit cluttered on the drivers side, though doing that would be ideal for stiffening the chasis would it not?

I was unaware that the main hoop had to be 180 degrees or less for total bends. I was under the impression that 1 3/4 was already relatively thick for building a cage. Although SCCA is not the sanctioning body up here in Canada they eventually seem to adapt overtime what SCCA does. It would be nice to be prepared for that.

The rule says 180 degrees +/- 10%. If you wanted to do that to the main hoop, I would be willing to bet that the tech wouldn't even bring up. Sometimes going up in size for the complete cage has its benefits. Check out the weight per foot of 1.5"x.120" and 1.75"x.095". Weight could be same or a little higher with much more structual rigidity.

The rules are a guide that techs do not seem to follow. I have seen real shit that has been passed by techs. If the welds are solid (clean) and the bends are nice, I do not see a problem. Main hoop would probably be a little safer on a side impact being tucked up to the b-pillars but more difficult for the door bars.

Bends in the tubes are not a bad thing if the bends are out, not bent in, away from driver. The cage is not a completely rigid thing. It must move and bend to absorb kinetic energy protecting the driver. Fab the door bars with mininum bends, 2, both out like a stock car ( \_____/ ). Try to avoid a 3rd bend allowing it to get to the main hoop ( see example below ).

Lots of fabricators use this type of door bars because the main hoop is so far behind the b-pillar or they are trying to get maximum clearance. I personally believe the bar has a structual weakness built in with the door bar bent in and then out. Under impact (load) the bar could continue bending in to the drivers seat. I am not saying this is a bad thing for all cars, just my opinion.

Dang, I'm busted! The 225 blew up so I went V8. I sold the car at the begining of the year to a guy on the East Coast. If I still made the same money and had the same expenses as I did in 2000 I'd still be racing the car.

You might also want to check on the bars that go behind the seat. Taller drivers need a little more seat recline room.

For example the autopower roll cage bows that bar back a few inches.

It matters in long road racing that you should be comfortable.

ed

:D This is me: http://www.angelfire.com/mo2/radrodder

Have they kicked you off of MoPax yet ;)

Hey Scott,

I see you are a Mopar guy. I am finalizing a long term project after many years for a good friend. Josh is aware of the car. It is a 66 Fury III. I have been waiting for the engine to get here for the past year so I could finish her.

Car has been mini tubbed, relocated leaf springs inboard, left room for the biggest drag radial tire made with 2" clearence for a bigger slick if wanted. Engine is a bored and stroked poly head 318, I think CID is close to 350 now. Engine dyno'ed with a sigle 4 barrel at 440 horse at 5500rpm. Project HP's is around 500. Has custom pistons, rods, cam. Has dual carb custom sheet metal manifold, custom headers, 727 trans with brake.

Has 100 shot of Nos, all the bling a new car should have. Installed new Dana 60, disc brakes all the way around. Finishing interior now with a custom Aluminum dash inserts and a full console. All electrical is in the console except lights for the dash guages. all replated interior chrome, new cage, all new glass and will have leather interior.

I gutted all heavy parts such as factory dash pods and lightened up the bumpers, hood and deck lid. Car was extremely over weight.

When I am done I will post some pics.

Now that's cool... very cool russ. Definitely post some pics. Someday, I'll get back to my Dart projects :(

One of the top National SCCA tech inspectors lives in my town, and when he did my annual inspection he definitely questioned the total bends being a little more than 180 degrees on my main hoop. Fortunately I followed the letter of the law, and used the next larger size tubing in my cage, so I was completely legal. He gave my car a very thorough inspection, an he even made me drill extra inspection holes in various right side tubes just to prove the wall thickness in each of them!

I am glad to see your tech is on the ball. I wish I could say the same here in the NW. I Have seen cars that had kinks in the bends, stick welded, and different diameter tubes used throughout the cage. I have seen cages in Miatas that had 5 bends in the main hoop and still use the mininum diameter tubes. I Have seen other Miatas done by another local shop that has a 16"x10" attaching plates and extra mounting points in the cage and was defended by saying " it is for saftey of the driver".


I think they are afraid of offending the owners of the cars so they will stay in the club. I get to worked up on this subject. I spend a lot of time in perfecting my bends, welds and follow the intent and the rule of the GCR so I can fab a really nice and safe cage. Then I see crap done by other shops that charge a few bucks less.

I wish driver's would demand more when it comes to their safety instead of saving a few dollars so they can put it to tires or similar! Enough of my ranting, show me more pics!!!!

A friend of mine bought a BMW 2002 and decided to redo the cage. It's a good thing he did. He actually found that some of the tubes were plain old exhaust tubing.

The new cage was a little more complicated than the usual club racer so the SCCA inspector started giving him a rough time asking him to justify why he replaced the cage.

My friend saved the section of tube that had the SCCA inspection sticker on it. It was one of the thin walled tubes.

The inspector stopped giving him lip and passed his new cage.

ed

As far as the tubing going to the strut towers through the firewall, this will be scca IT illegal. In IT tubes cannot pass foreward of the firewall, so if you want to keep your cage SCCA compliant (even though your running in canada) it might be a good idea to keep them behind the firewall.