Roll Cages vs. Roll Bars in higher class cars

[Jeff Lee]

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.

[J&P]

Originally Posted by Ian Hill

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

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

[Glenn1066]

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

[Jeff Lee]

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...

[Ed Wright]

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.

[Greg Hill]

Originally Posted by Jeff Lee

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.

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

[james schaechter]

Originally Posted by Jeff Lee

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.

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.

[Jeff Lee]

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?

[Ed Wright]

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.

[Jeff Lee]

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.