Carbing 6pt NB rollbar?

[Jace]

anyone else got one?

[Jace]

i didn't quite know where to post this, so here'll do.
okay well, i want you guys help yet again...
i'm not sure of how the Brown Davis bars and other actual roll bars fit and get fixed down, but the deal with mine is that it bolts to the floor behind the passenger and drivers seats, to the b-pillar where the seat belts attach (crossbar), and also to the sub-floor that's under the parcel shelf.
i was told by the previous owner that it's an NB bar (in my NA), which would explain the slight difference in width of the crossbar between the seat belt pillars (about 15mm between the mount and each pillar).
it's a very awkward spot to photograph in the car, so i'll provide a little explanation with each picture.

the bar is basically a 4 piece set up consisting of the roll bar itself, with two diagonal stays that bolt to the top of the bar at either side (these go through the parcel shelf to the sub floor/boot floor), and a nicely shaped crossbar that also bolts to the roll bar at each far side (also braces each b pillar/seat belt pillar).

seams like a pretty good set up, bracing in all the right places as well as harness mounts!

here are the gaps between what i'll call the crossbar mounts and the b-pillars.
not too much of an issue, i think getting right-angle plates made up to adapt should be easy and cheap enough.


this is where the diagonal stays sit on the boot floor (really crap pictures).
drivers side stay.


passenger side stay. second picture is from directly above the hole in the shelf. (you can see how huge the holes in the shelf are)



what i'd like you to help me with, is how to fix the diagonal stays to the boot floor.
what i've thought up, is having an adapter plate made, that will fix to the bottom side of the stays and have an offset surface to be more directly below the holes in my parcel shelf.
other than that, all i can think of is using long course drill bits and/or steel self tappers and bolting the stays directly to the floor (would most likely self-tap on stupid angles and not be all that safe anyway).
i'm looking to have it approvable for track days so i'd like it to be reasonably structurally sound.
you all seem to come up with pretty sweet ideas when it comes to your cars, so i figured you're the best people to ask.

also, is anyone able to tell me if my harness mounts would be FIA(?) and/or CAMS approvable? they can be seen in the pictures of the crossbar-pillar mounts
i'm hoping you can share some ideas with me so i can get this fixed down as safely and nicely as possible.
thanks in advance.

[bigdog]

Don't think you will get CAMS approval on these - the main hoop is too small in diameter, and they need to meet minimum specs on the steel used. Shame on the previous owner for butchering the rear shelf like that! You could adapt the bar to fit, but you'll need to weld plates to get to the seat belt mounts, and this will stuff the powder coat. If I was you I'd sell it to an NA owner and buy a BD or MX5Plus bar that can be approved.

[Jace]

yeah the shelf is rat poo.
yeah, well that's the other option. i was planning on getting it re painted anyway, but that might be a good option.
thanks heaps.