Brown Davis cage and CAMS Harness/FHR regulations

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takai
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Brown Davis cage and CAMS Harness/FHR regulations

Postby takai » Mon Jan 21, 2019 1:53 pm

A friend of mine has a freshly fitted BD cage in his NA, and had a scrutineer over the weekend almost knock him back for the cage. The issue is that the harness mounts dont appear to be symmetrical with the centreline of the seat, and wouldnt be on his unless the seat was half way into the trans tunnel.

This would be an issue under Schedule I 3 ii:
The shoulder strap anchorage points on the automobile shall be symmetrical about the centre line of the driver’s seat. When viewed from above, the angle between the shoulder straps shall be approximately 20°-25° as shown in Drawing I-8.

Manual available here: http://docs.cams.com.au/Manual/GeneralR ... 0-%201.pdf

Now the Schedule I(3) is a new set of regs in recent years, as there certainly werent such regs when i was racing in IPRA. But this will become a bigger issue as FHR regulations come in force in 2020 for everything down to Speed events. (https://www.cams.com.au/media/news/late ... eed-events)

My strap angles look like they would be much closer to centreline by eye, but i have no seat or harness in currently.

So, what sort of strap angles are other people getting with BD cages? Anyone else having issues with scrutineering?

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bruce
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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby bruce » Mon Jan 21, 2019 2:35 pm

Is it a BD bar (hoop on parcel shelf) or a proper cage (hoop and front section)?
BD bars were never certified. Cages are custom made and you would request BD (or whoever) to certify them.

To confuse things I've got a CAMS certified non-BD hoop. But it's more than a hoop as the front legs extend to the cabin floor (not the shelf) and are gussetted, with the rear legs extend into the boot floor (with reinforcement).

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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby track_addict » Mon Jan 21, 2019 5:47 pm

I have a BD bar. I e noticed exactly what you have described. I haven’t been pulled up in scrutineering, but I haven’t been to the track in 18 months. You could probably re locate the mounts for the eyelets fairly easily.


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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby greenMachine » Mon Jan 21, 2019 6:06 pm

Bruce, I stand to be corrected, but BD half-cages are/were sold new with CAMS registration (on request, at extra cost). Mine was bought second-hand and without paperwork, and I self-certified it prior to logbooking the car.

I am using the two supplied mounting points, and have had no issues from the scutes - I will have to have another look, but from memory they must be pretty close to the centreline of the seat. If you are having issues, I would just re-dill the mounting hole(s) to what might be required.

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takai
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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby takai » Mon Jan 21, 2019 7:23 pm

BD half cages are sold with CAMS certification and documentation, I know because the paperwork for mine is in the drawer next to me.

Seems like its going to be fun and games with them soon. Perhaps ill put another captive nut in when i pull the cage to do the fuel pump.

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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby CrazyRacer » Mon Jan 21, 2019 7:42 pm

I have noticed this problem too.

Even though I have the CAMS paperwork from BD for the bar I'm not happy to use the supplied harness mounting points. Its hard to understand how they could put them where the did as they don't line up with the seats. I did consider running both shoulder straps to the outer-most bolt (which is about central to the seat), but the other issue with them is that if you are tall and have the seat all the way back then the angle from your shoulder to the strap mounting location is too steep.

I ended up running the harness to the very rear nearly vertical section of the tray and fabricating some reinforcing plates to go behind the eyelet bolts. I'm not rapt with that solution either but its better than the BD harness mounts and in my case is temporary until another car with the proper cage is ready.

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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby bruce » Mon Jan 21, 2019 7:53 pm

Thinking back 20 years ago I remember pricing up the basic BD bar new. I think it was an extra $50/$100 for paperwork.
How old is the paperwork? Maybe the regulations have changed since then?
I honestly can't see how an old BD bar would stand up to scrutiny nowadays (and it seems they don't).

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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby takai » Tue Jan 22, 2019 10:17 am

bruce wrote:Thinking back 20 years ago I remember pricing up the basic BD bar new. I think it was an extra $50/$100 for paperwork.
How old is the paperwork? Maybe the regulations have changed since then?
I honestly can't see how an old BD bar would stand up to scrutiny nowadays (and it seems they don't).


These half cages are both under a year old, one was bought only two weeks ago; and I got mine in April last year.

Should say too, that the rest of the construction of the BD bars meets current CAMS standards.

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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby bruce » Tue Jan 22, 2019 10:41 am

They must have redesigned them since the old days. The only BD bars I see are the original older style 'roll bars'.

I think your original question needs to be put to Brown Davis. They supplied and certified the bar/cage (whatever you call it) only recently. I'd ask them to clarify or rectify the issue.

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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby takai » Thu Apr 04, 2019 12:00 pm

Minor update, scruit came and signed off on my logbook noted that they are getting close to the limit of lateral deflection, but fine in my case.

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Re: Brown Davis cage and CAMS Harness/FHR regulations

Postby manga_blue » Thu Apr 04, 2019 12:46 pm

I never used the mounting points on the flat bottom bar of my BD bar. I just looped the belts around that flat bar instead. Never a problem.
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