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I have recently purchased a 2006 NC to become a full time track car.
Sort term goals are some club track days and progressing to Supersprints and MX5 cup.

I purchased a Mazdaspeed rollcage with the belief that it would be suitable for this purpose but having started trying to understand the requirements for a CAMS logbooked rollcage, i am now feeling very confused.

Can anyone provide any advise as to if the Mazdaspeed rollcage would be CAMS compliant or advise about what is actually required?

This is a pic of it in the car but not bolted at the front mounts yet.

Have you studied Schedule J in the Cams manual to see if members & joints comply?

https://www.cams.com.au/motor-sport/reg ... quirements

RS2000 wrote:Have you studied Schedule J in the Cams manual to see if members & joints comply?

https://www.cams.com.au/motor-sport/reg ... quirements

I have it, reading it and trying to get my head around it.

RS2000 wrote:Have you studied Schedule J in the Cams manual to see if members & joints comply?

The joints look like they comply.

I guess a call to CAMS technical department may be the best path.

The first thing that I note is that there is no diagonal in the main hoop, and no rear bracing. The diagonal is a necessity, as I understand it, and I think the rear bracing probably also. No door bars either, but I don't know if they are a requirement.

There may be material issues, sizing, thicknesses etc given that it obviously is not produced here. Generally bolted joints are frowned upon by CAMS, though a 'properly engineered' joint design would be accepted, whatever that is and however you demonstrate it.

If you are going to get a CAMS logbook, there are two steps. One, get the cage registered by CAMs, then get the car inspected by a CAMS scrutineer for the logbook. I think that is the sequence, but in your shoes I would first have a talk to the scrutineer and get him to look at the cage you have and see what he says. No point in submitting paperwork if (worst case) he says 'no way no how' with that cage, and if he says that certain things are required then you are probably heading in the right direction. Maybe.

Have you looked at the certification requirements on the application - they are written so that the person certifying (applying) is effectively stating that they personally manufactured the cage to comply with CAMS specifications. That may or may not be a consideration ...

My guess is that you are going to have to spend money on that structure to get it up to standard, unless you are a capable welder. In your shoes I would be pricing some alternatives so that you know how much is too much to spend on that one. In fact, I wonder if you wouldn't be better off cutting your losses and getting one made - Deckspeed and MX5 Parts spring to mind, and AGI. It will save you a lot of stuffing around, and may even turn our cheaper than a significant reworking of that cage, and you know that you getting something that will pass muster.

Thanks for the feedback Greenmanchine.
There is a lot of info and for the noob to CAMS specs it is a little confusing.

PS. There are side intrusion bars on the cage, you can just see it under the steering wheel in the pic but the other issues are looking complex.

Snowmotion wrote:I guess a call to CAMS technical department may be the best path.

Good luck with that!
See section 13 in Schedule J for Open cars. Stays may be rearward OR forward of main hoop in open cars, but they have to be straight, so I'd say your lateral bars wouldn't be considered as front stays.
As greenMachine said, it states that a diagonal is required, but you could add rear stays & put a diagonal between them to comply.
As well as joint design & member sizes, you need to check minimum feet & bolting requirements.
Cheers

CAMS were actually quite helpful when I built a full cage for my Datsun last year, replying to emails fairly promptly with helpful advice and answers. And when done, I sent off my logbook application on a Monday afternoon (admittedly, complete with the $75 extra "express processing" fee), got a reply Tuesday morning to say my logbook was in the mail, and the logbook turned up in my letteerbox on Wednesday. Just as well, I was leaving for Bathurst on Wed arvo

Anyway, some stuff you need to consider:

Size and material used - Must be CDS or CDW "plain" steel (ie not an "alloyed" steel like Chrome Moly), main hoop must be 1 3/4" and 2.5mm wall thickness, other tubes can be 1 1/2" and 2.5mm wall thickness. Its going to be hard to work this out, unless you can get specifications from the manufacturer ? If you measure the size of the tubing and it isn't exactly the sizes mentioned, chances are its not correct grade.

Bending - tubes must not be crushed / ovalised by more than a certain %-age (can't remember exactly, its in Schedule J).

Mounting feet - must be a certain area and thickness (3mm thick, area varies according to weight of car). Bolt "pattern" must also meet regs in Schedule J.

Number of bends in front legs - no more than two, can't really see what yours are like.

Joints - Schedule J is very specific about what joints / how many joints are OK. Can't really see if yours would comply or not.

As mentioned, lack of backstays and lack of a diagonal in the main hoop are just two of the obvious problems with your cage.

What I did when I was designing / building my cage was read Schedule J (a few times......) and make notes on the parts that I needed to comply with.

Realistically, it could be quite difficult to get your cage complied. I'd be inclined to sell it and get one made / buy one off the shelf that comes with a certificate from manufacturer.

Thanks for all the replies and advice.

I sent an email off to the CAMS Technical team and had a very quick replay by phone within the hour. Vary impressed with the response. The advise was that there are some aspects of the set up that could be modified to work in the regulations and others that just won't pass.
The main hoop could be adapted but would require a) pair of rear stays b) the center horizontal bar removed and one piece diagonal welded in place. The forward cage will not pass as they do not allow for bends in the arms. This means the side intrusion beams will have nothing to fix in place.

So the next step is to make a good plan and decide if I want modify the bar or find another solution. First step is to mount my race seat and see what height rollbar I need.

My first step would be to determine what material has been used. If you can't be sure of that, you have no chance of getting it logbooked no matter what modifications you make to it.

My understanding (and I stand to be corrected) is that you wouldn't have to remove the harness bar and put in a diagonal. You could put the diagonal between the backstays when you add them (from top of driver's side backstay to bottom of passenger's side backstay), this is an acceptable alternative.

As 1600Dave says, I don't see why you would have to remove the horizontal member?
See drawing J-19 in Schedule J, Section 13.1 a). The horizontal between the main hoop legs in your case, adds to the strength of J-19 set-up.

The advise I was given was that the diagonal needs to be one piece. The cross member could be put back in in 2 pieces.
There are mounts for the harness on the lower cross member so it is not a major problem to do this.

Either way I will take my time to make the next decision.

my $0.02 is to do it once, and properly.

The car doesn't have to be expensive or fast to have fun. You don't have to be fast to have fun.

But you do want to be safe. Take your seat and car to a pro and get them to build the cage up around you and your driving position (+ passenger seat if required). You'll never have to change it, and you'll be happy knowing it's all up to spec.

In the scheme of a race car, it's not going to be the biggest expense anyway.

I have a NC which I used for the last 3 rounds of MX-5 Cup.
It has a welded in half cage that was made and welded in by Daniel Deckers.
It was done before I bought the car but was not certified at that time as the previous owner was only doing supersprints.
I bought the car with the intention of racing in MX-5 cup so I took it to Deckspeed at Padstow and got them to arrange for the half cage to be certified and for the car to be logbooked.
Suggest you might get Daniel to do the same for you.
If you only want to do MX-5 cup you could go the AASA passport route. It is much the same as CAMS logbooking but much cheaper.
I went with cams as AASA recognises the cams logbook and licence but CAMS does not reciprocate. And I thought I might do some CAMS racing at some point.

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I can get a better photo on Sunday.