View Full Version : Roll Cage Rules

11-03-2017, 06:14 PM
We recently bought a BMW E36 and the welds on the roll bar are a mess.
I'm redoing the cage and just wanted to know if riser boxes are legal (see image). The cage would be welded in place rather than bolted. I was hoping to reuse some of the main hoop.


11-04-2017, 12:19 AM
If done right, no issues that I know of. Have seen plenty of card done this way.

11-04-2017, 07:02 AM
Thanks for the info.

Gunter Schmidt
11-04-2017, 09:56 AM
Please read the the current rules.

6.5.1 Mounting plates shall be no thinner than 1/8in and no thicker than 3/16in with no single edge longer than 6in and
with back-up plates of equal size and thickness on the opposite side of the panel with the plates through-bolted
together using a minimum of three bolts per mounting plate. The minimum acceptable bolts shall be SAE Grade 5
of 3/8in diameter. Mounting plates may be welded to the car. Wherever possible the mounting plate should be
shaped to and welded to a vertical portion of the car. Mounting plates shall not penetrate the firewall at any point.
When the roll cage is attached to the floor, no contact plate on the Car shall measure less than 20 sq. in on any
given plane.

6.5.2 On specific models of Cars where the floor construction will not permit a contact plate of this minimum area to be
installed application shall be made to CASC-OR for a waiver to this rule. This will be noted in the Car logbook.

The following procedure is approved for increasing the height of existing roll cages not meeting the 2-inch helmet
clearance requirement:
a) The old main hoop shall be cut off near the chassis mounting and either a new main hoop of equal tube size or a
section of equal sized tubing may be added.
b) Inner tubing shall be used to mate all sections together.
c) All braces shall be a maximum distance of 6 inches from the top of the hoop.
d) The inner tubes shall be rosette welded at three points near the top and three points near the bottom. Refer to the
diagrams herein.

11-04-2017, 12:12 PM
I read the rules...but I don't see anywhere (including in your post) where it addresses riser boxes as mounting plates.

Are you saying the only acceptable way to reuse the main hoop is as per rule 8.0?