Roll Cages vs. Roll Bars in lower class cars
 

Hello All,
I was just wondering if you guys could shine some light on this subject for me. I've been noticing lately that alot of the lower class cars D thru K or so are actually using a roll cage when its not really needed per the ET breaks. I'm guessing the cage stiffens up the chassis and could prove better 60' times. Is there a proven advantage in the 60' or something?

Re: Roll Cages vs. Roll Bars in higher class cars
 

It does stiffen things up. Some of the cars cross over to super stock in a class that required a cage. But me, I am looking to put one in my stocker because of the increasing speed differences. 145mph plus? vs my 110mph I just see it as safety. I would like to hear what the weight difference has been from a mild steel roll bar vs. a chrome moly roll cage? No front bars of course.

Re: Roll Cages vs. Roll Bars in higher class cars
 

3 years ago took out a 6 point MS roll bar, installed an 8 point CM roll cage Aprox. 20 Lbs. lighter even after adding more tubes. This is just my opinion but given the choice I see no reason not to go with CM, yes it's more expensive and requires tig welding but think back to the first question anyone asks' when looking at a car.... "is it MS or CM?" On a full cage and frame the weight savings are substantial.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Don't forget that when you use a CM cage instead of a 6 point MS roll bar the tubes can be a smaller diameter and thinner wall which saves some weight in the overall installation. Consult with a chassis builder for specifics but the weight savings is pretty significant since several CM tubes in the cage can be less than 1/2 the required wall thickness of MS. As buzzinhalfdozen points out his CM cage was lighter than his MS roll bar. Generally speaking a properly sized 10 point CM cage weighs about the same (within 10 lbs) as a 6 point MS roll bar!!!

Re: Roll Cages vs. Roll Bars in higher class cars
 

CM is the way to go. Lighter. Stronger. And CM doesn't rust!
My mistake when I built my CM roll bar for Stock class was not using a drivers side rocker bar. I thought the fact I had a CM bar everything would be fine. When I switched to SS class, I had the roll bar converted to a roll-cage. Still no rocker bar. In the end, somewhere along the way, the (slightly) rusty floor separated from the rocker, causing chassis problems. Now I'm building a complete back-half (CM) with 4-link. I may not have gone this route had the chassis remained true.

Re: Roll Cages vs. Roll Bars in higher class cars
 

I am finishing up an 8,50 cert CM cage in my K/.S car. Added safety, lighter than a MS roll bar and room to grow/move up!

Re: Roll Cages vs. Roll Bars in higher class cars
 

The rocker bar is required now, even on the 10.5 cars

Re: Roll Cages vs. Roll Bars in higher class cars
 

I have c/m cage in my pure stocker when I built it I was and still going to K/S.I went with cage because I figure cage will eventaully be required,and as others have said c/m cage weighs about same as mild roll bar.
Mike Taylor 3601

Re: Roll Cages vs. Roll Bars in higher class cars
 

Thanks for the replies guys. One last question. Is it required to cut the top off the car to install a cage?

Re: Roll Cages vs. Roll Bars in higher class cars
 

No you do not have to remove the roof. The top portions of the bar are tack welded in the car and the lower legs are dropped through the floor sections so you can get a 360 degree weld on all of the top portions. Afterwards the bar is raised and secured to the floors.

Re: Roll Cages vs. Roll Bars in higher class cars
 

The only downside to runnig a cage is that it has to be certified every 3 years. A roll cage that is not NHRA certified is only good to 11.50 et, a roll bar with a un-modified floor pan is good to 10.00 et. I would still put a roll cage in. $0.02
Larry

Re: Roll Cages vs. Roll Bars in higher class cars
 

My understanding is that the Cage only has to be certified if the car
is fast enough to REQUIRE it to have a cage.

My car has had Cage and been race continually for 18 years and show
No Flex of Body unlike a lot of my other cars. I believe that it further makes
the car stiffer and easier to tune chassis. We did remove Windshield to
Fab it and get everything to fit as close as possible.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Are you sure about that? Makes no sense................

Re: Roll Cages vs. Roll Bars in higher class cars
 

Thanks Jeff, I thought you might be able to do it that way but wasn't 100% sure.

Re: Roll Cages vs. Roll Bars in higher class cars
 

I also think this is incorrect..... No cert. required on a cage until a 9.99 et is attained...
I run a cage, no cert. @ 10.31 et....

Re: Roll Cages vs. Roll Bars in higher class cars
 

ditto

Re: Roll Cages vs. Roll Bars in higher class cars
 

There is a track in WI that states that this is a rule, but I just looked it up and the rule specifically states that you only need a cert if you are running 7.50-9.99. Sorry for the misleading information.

Re: Roll Cages vs. Roll Bars in higher class cars
 

also, contradictory to what was posted below and another post a couple months ago on this board, that overly bashed a chassis builder for not fully welding the cage on the halo attachment points. the cage does not have to be fully welded. as long as the cage is properly fit and welded properly 3/4's around the tube and corner gussets are added then it will pass tech with flying colors! gussets can be in the form of small corner plates or small diameter round tube. this is how chassis builders are able to tuck the cages up to the headliner real tight on cars without cutting holes in the floor! those silly little gusset plate or small diameter roll bar tubing welded in the corners aren't just there for looks.

don't let the flashy paint fool you!

Ian

Re: Roll Cages vs. Roll Bars in higher class cars
 

Interesting...

Re: Roll Cages vs. Roll Bars in higher class cars
 

Do you have to run a window net in a stocker that is not required to have a cage but does?

Re: Roll Cages vs. Roll Bars in higher class cars
 

Once you install a cage you have to follow cage rules. That means nets are required. NHRA looks at it that once your at that level of having a cage, even if it runs 15's, you have to conform to all of those safety rules.
Same as seatbelts. You can have a 15 second car with OEM belts and leave them there forever. But once you put aftermarket belts in, you have to recert or replace every two years.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Where are you getting this from?Where in any rule book does it state this?There are ways of welding these joints 100%... anything less is hack

Pete

Re: Roll Cages vs. Roll Bars in higher class cars
 

Jeff I have a cage in my ss/ma 65 Chevelle for the past 8 years without a net, passes tech at both Divisional and National events no problem.

Glenn

Re: Roll Cages vs. Roll Bars in higher class cars
 

I believe if you consulted with NHRA you would find "Passing tech does not set precedent or validate a violation of the rule book".
Happens all the time. And then one race you've traveled 1200 miles too...:confused:

Re: Roll Cages vs. Roll Bars in higher class cars
 

Jeff, I believe you are mistaken. My cage is certified to 8.50, it's not required unless I run 9.99 or quicker or move to a class that requires it. SS/JA is the highest class that doesn't require it. I don't have to put the window net in unless I move up to SS/IA or one of the close by GT class, or dip into the nines. It's in the trailer, but have never been asked to install it. I have not run Div 7, but have 3, 4, & 5.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Jeff, you don't have to have a net unless you run under 10 seconds even with a cage.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Maybe that was the case in some divisions or when you raced last, but it does not seen to be the case now.
We inquired about window nets with a cage and the tech official said that if the car required a cage, yes, but if you had a cage that was not required it was not necessary.
A friend of ours had a P/Stick biscayne with a rollbar and it didn't even need new belts every 2 years when he ran it! Go figure.

I guess that is why the tech guys in each division have email. I would not follow my tech advice or anyone else's here. Your Division tech person is the one that needs to answer these. I doubt if a print screen from any of us will save you on any ruling disagreements with tech. LOL

I do think a moly cage is the way to go. My 2 cents.

Re: Roll Cages vs. Roll Bars in higher class cars
 

James is correct, you better check with your DD. I just looked at my '08 rule book (and I doubt anything has changed in this regard but check the online & current version). Under window net, it says "mandatory on any full bodied car required by the rules to have a roll cage".
When I look under both Stock & Super Stock, the rules define which classes or ET require a roll-cage but allow a roll-cage for slower vehicles. There is no reference one way or the other that a net is required or even optional. So basically one could argue that since the rule is not clear, having a net could be an infraction in a class that does not require a roll-cage.
The rule book is full of ambiguities. For example, the rule in paragraph 1 above states a net is required on any full-bodied car..." So I guess trucks don't count? Obviously they do. But somebody with a truck might make that argument one day.
I would still contend that roll-cage = net even on a 15 second car because you have elevated the chassis to the level of a roll cage so you have the net also. Same as I said about seat belts. Once you elevate the car to the level of aftermarket SFI belts (even on a 15 second car), you buy into recert or replacement every two years.
I'd be willing to bet that if I asked NHRA for clarification on the net issue in a slower car with a cage, the net would be mandated. But don't worry, I'm not asking!
But why would one want a cage and not a net?

Re: Roll Cages vs. Roll Bars in higher class cars
 

This sentence: Under window net, it says "mandatory on any full bodied car required by the rules to have a roll cage". answers the question.
And, yes I did asked about it. Why have a cage and don't want to use the net? Just prefer to not screw with it. If I want to put the car in a class where a cage is required, I have it, and the net, multi/layer fire suit, neck collar, and gloves.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Ed, I suppose when everybody throws the "safety" clause out there (wheelie bars, roller rocker arms, 4WDB, etc.) it's convenient when trying to get something approved. When it's not convenient towards getting something approved, it's a hassle.
I've had roll-cages with nets. I really can't understand why somebody would spend the time and money on a full cage and skimp on the $55 net and GM seat belt latch. One click and it's latched.

And to Ian Hill, I looked all over the rule book. Can't find any reference to "3/4 weld" with gusset" being adequate. Can you point the readers here to where in the rule book you are referencing? I'm no engineer, but I'm sure some stress testing would prove an incomplete weld with a gusset isn't nearly as strong as you would like to think it is. I do know this, if I was looking to buy a car and it was full of incomplete welds, I wouldn't buy the car. That in itself tells me a bunch of corners have been cut.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Ed;
Don't nets have a cert, expiration date? If so then the net that you have in case you "want to put the car in a class where a cage is required" may be out of cert. at that time..... ;-]

Re: Roll Cages vs. Roll Bars in higher class cars
 

Only mesh type nets have to be replaced every two years.
The more common ribbon type does not need to be replaced .
The rule book states window nets are required on all cars REQUIRED to have a cage.
This may vary by Division or track,but in so far in D1 cars that have a cage ,but are NOT REQUIRED to have one, have been alowed to run without using a net.
I have several customers that have told me this is the case.

Also rocker sill bars are still not required on non SFI spec roll cages [8.50 and slower et] on cars with stock floor pans and dont have more than 6sq ft of removable floor for trans removal.
I,d still recomend one ,but the rocker and the dash bar are not required if the floor and rocker is not modified.

The only way to build a cage is to WELD 360 DEGREES and use gussetts.

Chrome Moly will rust just as much as mild steel ,once the mill finish is sanded off for painting ,if left exposed.

Re: Roll Cages vs. Roll Bars in higher class cars
 

I put a full cage in when I built the stocker just for my safety even though it was not required. . I would not have it any other way with the speeds of the new Stockers. It is also nice to have if you ever want to run Superstock.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Maybe the seatbelt rule is interpreted differently from division to division, but I have a P/SA that has an aftermarket belt dated 1994 in the car. The person I bought the car from went through NHRA Div 1 tech many times with these belts and so did the previous owner from about 1999 until 2007/8 or so.

I passed tech in IHRA Div 9 with the same belt in 2010, plan on taking it through tech again with that belt in 2012. I will inquire within the sanctioning bodies just to be crystal clear though before next season starts.

I would think a quality aftermarket belt and latch is about 20 times stronger and safer than a 44 year old factory original belt.

Re: Roll Cages vs. Roll Bars in higher class cars
 

Your logic is sound but the rule book is quite clear. The book does not differentiate between classes, aftermarket belts must be re-certified every two years.