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Author Topic:   Used cage
chevelle
Dirt Full Roller

Total posts: 71
posted December 29, 2003 04:29 PM  
Just curious on what peoples opinion on tansplanting a used cage. I might have a line on a car with cage that was built and ran about 7-8 years ago. My brother knows the history on the car. The cage was built by a local chasis builder. The best part is that it will cost little or nothing for the entire car.

BK19
Dirt Freak

Total posts: 477
posted December 29, 2003 05:00 PM  
My concern would be the strength of the cage. If it has been sitting that long I don't see it being a strong as it was because of rust. I am not a fan of reusing a cage due to having to cut the roof off to get it back in the new car. Especially if it is a subframe car. The roof is a part of the structural integrity of the car and it is weakend greatly when you chop it. If you do it, torch the frame around the tubing then grind it down to get it back to the origianl tubing so you don't lose any height or strength in the tubing. Then make sure you do a good job of reattaching the roof, I have seen way to many fly off during a flip and it is scary. To me it is more trouble than it is worth but maybe not in your case. Just make sure you check it for rust REAL well, it will rust from the inside out too so check it good.

zeroracing
Dirt Forum Champ
Total posts: 1875
posted December 29, 2003 08:42 PM  
just look it over GOOD for rust. that would be my concern other than that i ran a nova and it was tied togthere so it was a full frame and also the cage your addind will give it the strength so dont worry about cutting the roof off, i never had any problems with any of my novas or seen anybody have a problem. you should not use a stock roof or pillars as an important stregth point of your car. that is not a safe idea.

dirtrace
unregistered Total posts: 1875
posted December 29, 2003 09:13 PM           send a private message to zeroracing   Edit/Delete Message   Reply w/QuoteBBBBBB
yeah that post kinda confuses me??

Im building a nove I stock now, and first I connected the subframe, then I started caging it, cutting out what wasnt needed. now the body, roof is sitting attatched at the front window posts and sitting on boards to hold it up above the cage, no strength in the body there?

Jeff

zeroracing
Dirt Forum Champ
Total posts: 1875
posted December 29, 2003 09:45 PM  
like i said it is not a strength part of a race car. or at least one that i would ever drive. also xing your frame will help alo.

racerguy500
Dirt Maniac

Total posts: 168
posted December 30, 2003 06:34 AM  
If you tie it all back together and add some braces the tubing will be supporting it. On a factory car, the roof ties it all together. On a 4 point cage and even a six it is not wise to cut it, if you can run front and rear loops with supports it is ok. Look at cars and the way the are built and what happens with hard crashes, it is A FACT that the roof is there to tie it all together. Look at any car that has been jumped over a hill and it will flex and bend right in front of where the front roof pillars connect to the firewall. Hmmm, wonder why that is???????? Being as though this is under the pure stock/bomber tech, I assume he can't run alot of support braces. If you ever get the chance while you have the roof off, jack up one corner of the car and see for yourself. Or jack up all 4 corners and stand in the car and bounce. It will flex all over the place. The design and shape of the roof is like that for a reason. The front pillars have several layers of metal for a reason also. Like I said, if you tie it all back together you are ok but I don't see that happening in a bomber type car. In fact our track won't allow you to run in that division if you have cut the roof off and reattached it. Wonder why that is too??

odb93
Dirt Forum Champ
Total posts: 537
posted December 30, 2003 09:56 AM  
Chevelle.....That is exactly what I have done. I was given an old race car. We took a wizzzzzzz wheel and cut the frame where the cage mounted. Then we set the cage in the floor and removed the frame from cage.

Cleaned the cage up with a wire brush and we had to replace two tubes in it.

Then set it in the new car and welded away.
(We did cut the roof off the car)

The only part of the car that is left as far as sheet metal anyway is the floorpan, firewall and shell.

The rest is gone.

The only advice I can offer is to make sure that your cage is tall enough. You may need to add a little to it. I wish we would have.

[This message has been edited by odb93 (edited December 30, 2003).]

zeroracing
Dirt Forum Champ
Total posts: 1875
posted December 30, 2003 03:49 PM  
if you build your cage right you should not use the roof as a support, i had two novas, and there are about 4 cars just about like it and all of them have cut the roofs, and i know of qiute a few that have rolled and are just fine. have you ever taken off a roof, not very much support in a piece of steel is there, it is pretty thin. that is just a very bad idea to use any parts of the body for a support. just build your 4 point or your 6 point cage really good and out of the right stuff and you will not have any problems. if you use the roof for a main support then i am sorry but your asking for alot of problems, ever seen a car rollover(a unibody) without a cage in it. there is usually nothing left. ever seen one get hit hard the roof bends pretty eaily. i have cut my roofs off and put in the cage then put the roof back on and still bent it up in a crash.(cage was fine and the car was never effected by it just body bent up).
and about roofs flying off, that is not a big deal as long asthe driver has arm restraints, have you ever seen a topless car run, no saftey problems there.
if you build your car right you will not need the roof and post as a part of the support. it is not a very good idea, talk to any body that has been around enough racing, or has built cars that have taken alot of flips, the last thing you want is to use the stock body as a support.

racerguy500
Dirt Maniac

Total posts: 168
posted December 30, 2003 08:20 PM  
A. I DO NOT BUILD THEM TO SUPPORT ANYTHING!!!
B. THEY ARE BUILT THAT WAY AT THE FACTORY!!!!
C. IT IS A FACT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
D. I DO THIS FOR A LIVING AND HAVE RESEARCHED IT EXTREMELY WELL TO IMPROVE CUSTOMERS SAFETY AND A GOOD HANDLING CAR!!!!!
E. AND YES, I HAVE DONE IT BEFORE, LIKE I SAID, IF IT IS SUPPORTED WELL ENOUGH IT IS OK, BUT I DO NOT ADVICE IT BECAUSE IF YOU DON'T DO IT WELL ENOUGH IT CAN COME BACK TO HAUNT YOU.
F. ON THE CARS THAT I SAW THE ROOF FLY OFF OF THE SAME GUY THAT WELDED THE ROOF WELDED THE CAGE. HOW SAFE WAS THE CAGE AT THAT POINT?
G. MOST OF MY CARS ARE JUST THE SKIN BUT THE CHASSIS IS SUPPORTED AND BRACED TO DO ALL THIS. IN ENTRY LEVEL, MINIMUM CAGE CARS IT CAN BE SCARY.
H. IF YOU READ WHAT I SAID YOU WOULD SEE THAT I SAID IT IS OK TO DO IF DONE PROPERLY. CALL DETROIT IF YOU HAVE A PROBLEM WITH IT BEING A STRUCTURAL INTEGRITY PART OF THE CAR. I DIDN'T DESIGN IT THAT WAY BUT THEY DID.

24s52
Dirt Maniac

Total posts: 122
posted December 30, 2003 08:42 PM  
try putting a single loop from one side of the frame up to and across the roof to the other side of the frame and holding it up to the roof with two u-bolts. That's the most roll bar I ever had until I built my enduro car. Now I feel incredibly safe with my whole cage. In some SCCA events I have been in all you needed was a car straight from the factory. No cage and just the regular seat belt. Cut the roof or not it does tie the car together to some extent. The key is just getting everything RIGHT however you do it.

zeroracing
Dirt Forum Champ
Total posts: 1875
posted December 31, 2003 09:36 AM  
well how strong the weld is is a different story. dont get all bent out of shape. i am sorry if i offended you but i am jsut saying the roof should not be a important part of your car. weather or not it came from detroit as it or not, your desing should not use the stock body as part of the strength.
and most all the cars i see the roofs fly off are pop riveted on, not welded.

wizzard
Dirt Freak

Total posts: 306
posted December 31, 2003 09:44 AM  
just my 2cents worth as far as strait from the factory go's the roof does ad suport if ya ever get a chance look at a hard top car then a rag top the rag top will have a [lot] of extra bracing under neth it so if the roof dosent ad support why did they ad extra goody's to ragtops.but i do understand that if ya tie every thing together with a cage it shouldnt make that much difference

[This message has been edited by True Blue (edited December 31, 2003).]

racerguy500
Dirt Maniac

Total posts: 168
posted December 31, 2003 05:46 PM  
You don't get it Zero, I did not and am not building them that way. They ARE that way from the factory. You jeopardize that when you whack it and being this is in the pure stock/bomber section I assume they can't do alot to tie it back together. Now if you want a really strong car, weld the roof to the cage. Tell me it doesn't matter then when you see the difference. And yeah, it does bother me when I see on here that I did this and I did that and it worked for me. That NEVER makes it right OR safe, that just makes it an opinion. Maybe we should have both got more details but I am thinking the guy could get a cage built right for a few hundred bucks. And maybe he could be hurt for next to nothing. Sounds better to me to spend the few hundred. And EVERYBODY quit saying that I am building the roof to be a part of it, Detroit did that, I just choose to take advantage of it, if you don't want to my cars will get you in the corner when you think all is good.

zeroracing
Dirt Forum Champ
Total posts: 1875
posted December 31, 2003 06:16 PM  
i think my car was quite a bit safer than any other street stock i have ever seen so you can talk all you want about not cutting the roof. i know detroit made it that way but i would cut it out, use tubing and then just pop rivet the roof back on, then your strength is from the tubing not the old roof, which there is no way of telling how stong it is.
build your cars how you want, if there ok and no saftey problems then keep doing it, but i know my car was extremly safe.
so you can cut the roof and have a safe car.

Eljojo
Dirt Forum Champ
Total posts: 968
posted December 31, 2003 07:14 PM  
JoJo says--full fram cars are fine to do home shop cage swaps with the roof laying out back on a pile of snow. Unibody cars should never have the roof removed UNLESS there is structural integrity built into the cage-NOT FOR SAFETY for replacing the structural integrity of the chassis.
Personally I like to leave the tops on AND run a channel down the rocker panel, tieing the subframes together. But then-I like a car with minimal flex.

racerguy500
Dirt Maniac

Total posts: 168
posted January 01, 2004 07:18 PM  
Ok, here is what I am saying one more time, this is on the bomber/pure stock post. You have a street stock which obviously allows more bracing for one. For two, if you are pop riviting your roof on, that is the DUMBEST thing I have EVER heard of. And finally, read and understand what you read. I have said the same thing and you somehow seem to think that I am building the roof as a part of the thing when in fact it came that way, I just choose not to lose that benefit when possible. I also have said several times that it can be done safely if done properly. But I am glad that you have one of the safest you have ever seen. But you should look around more, you have one of those roofs that is going to go flying off. Once again, the I did it, and my car is this way theory goes right out the window. Fix your roof before next year and have some good, fun and safe racing.

zeroracing
Dirt Forum Champ
Total posts: 1875
posted January 01, 2004 08:03 PM  
the way you worded you first post you implied that you use it for structural integrity, i know it came from the factory that way you did not disign it that way, but you implied that you still use that for alot of you structural integrity, and i am pointing out you should not trust any factory body part for alot of strength in your car. you should build extra bracing so that you do not have to rely on the stock roof, what if that car was rolled over before nad fixed at a body shop, they just heat it up alot of the time and pull it back out, not exactly keeping the strength, also what if it is rusted under the bracing and you can not see it, most people cut out their bracing anyway.
about the pop rivet deal aparently you have never seen a modified or a latemodel or in fact most all street stocks, they have the roofs popriveted on. if you spread the load with some pop rivets then you will be fine plus you can take your roof off for repairs, or in a hard crash it pops off the rivet so the roof is not destroyed(yes my roof would flex if the car was it my cage was under the skin and would not) that way you can repair the car much faster and it will look better. if you roll the car the roof can come off then but if you wear arm restraints there is no worries.
there is not a real saftey advantage with roofs, why do alot of cars around here run topless races. there is some but most all flying objects that will hit the driver will come threw the windshield, due to trajectory if there is no roof and something flys and hits the car where the roof was, it will hit the rear deck not the driver.
the roof only protects the driver from flying debry for about the first 4 inches ifthat. trust me i know this stuff ok.
i dont have to reweld my roof because i would not do it first off, and secondly now i drive a mod so i dont have the street anymore.
but what do i know compaired to you i mean you have been racing longer than i have been alive by a number of years.



speedyd1
Dirt Maniac

Total posts: 170
posted January 07, 2004 06:25 AM  
i agree with both - we typically cut the roofs off when building a cage. it just makes it easier. we put the car up on an i-beam frame, level and square the car, and weld bracing bars from the rack to the chassis etc before we ever cut anything. it works great for unibody cars. cars with frames arent so bad. our cages attach directly to the chassis going thru the stock sheet metal and thus are not effected by the whole roof thing. the body is there for just looks at that point and is totally irrelevent.just make sure you are good enough with the welding to put the roof back on. we use at least 1" flat bar behind all joints when we reassmble the roofs and mig them . it makes a good strong joint and cant be seen when the car is finished and painted.

GrumpyII
Dirt Roller

Total posts: 8
posted January 07, 2004 09:36 AM  
If you cut the roof off, yes you lose structural strength. Thats why you WELD THE CAGE IN!! Once you attach a roll cage,if its done right, you're right back to square one. If you're not comfortable with your own welding skills, pay someone to do it right.
Everyone knows someone who thinks they are able to weld, that really can't weld worth a darn. Maybe track officials should be more concerned with doing pre race safety cage checks, than worrying about who's cheating on the tech end.

[This message has been edited by True Blue (edited January 07, 2004).]

wizzard
Dirt Freak

Total posts: 306
posted January 07, 2004 11:22 AM  
thats it grumpy ive raced several different types of racin and stock car is the only one that ive entered and they dont do a full on safty check.ie brakes seatbelts cages. some of the drags ive been to wont even let ya unload the car till its inspected same with alot of the 4x4 events

outlwam248
Dirt Newbie

Total posts: 3
posted January 08, 2004 04:55 PM  
i've worked in the auto-body industry for about 11 years and know that the roof does add to the structural integrity of a car but detroit didnt design them for dirt track racing so once you put the cage in the roof dont do nothing whether you cut it off or not i have one fiberglass roof glued on a bomber and one riveted on a super-street never any problems and the super street was rolled 3 seperate times before i got it and it never came off
your cage is your support not your roof

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