[BGKP Saab 900] Mocking Up the Roll Cage

We’ve introduced the BGKP NG900 and covered stripping it down to its bare elements. Over the next month the focus will be on safety prep—primarily the racing seat and the roll cage.

Mounting the Seat

Our experience with the Civic taught us that mounting a seat may not always be as easy as expected. Consequently, that was priority number one now that the Saab was stripped. Thankfully, mounting the seat in the 900 was pretty straightforward due to its spacious interior.


The mounting locations for the stock seat were the perfect width to accommodate our seat, so Hassan was able to combine our seat sliders with the original seat mounts. This made mounting the seat a breeze and saved us a bunch of time, which was severely lacking during this build.

Roll Cage

Similar to the seats, the lessons learned from the Civic combined with the larger interior of the Saab made planning a lot easier this time around. The order of operations was: main hoop, diagonal support, harness bar, halo hoop, rear supports, a-pillars, door bars then dash bar. We had picked up the steel a few days earlier, so it was time for us to get to work.

Main Hoop

Working the plan, the first step was to make the main hoop. This is the most complex piece of the cage with the highest number of bends. It is also the attachment point for nearly every other piece of the cage, so it has to be as close to perfect as possible. We measured, and measured again, as we meticulously planned it all out.

We marked up the tubing, threw it in the bender, and started bending. We let each bend sit for a couple of minutes once we thought it was at its desired angle, just to make sure there was no additional rebound. Once we were convinced, we moved onto the next bend, making sure each time that the tube stayed level and in the same plane. An hour or so later we had a main hoop that was ready for fitment, and not to brag, but I think we did a damn good job.


Diagonal Support

The next step was to start “filling in” the main hoop. The first step of this sub-process was to cut and notch the diagonal support for the main hoop. The diagonal supports the main hoop in the event of a rollover and prevents the cockpit from collapsing into the driver. Once the diagonal support was in place we moved on to the harness bar.

Harness Bar

In order to determine the proper height for the harness bar we temporarily mounted the seat to ensure we had the proper angle for the shoulder straps. After a couple cuts, a few notches, and a handful of tack welds, the harness bar was in place.


It was a productive first day, but we knew if we were going to get this car done for Gingerman we had to be diligent, so we continued on. The next step was to get the halo hoop mounted. We designed the halo based on the width of the main hoop and how close we wanted to come to the factory crash support over the windshield. With all of the dimensions determined we got to work and were, once again, cutting, bending, notching, and welding.

20170624_Work_Grass Lake_1997 Saab_BGKP_Cage_Halo_3

The halo hoop is where the benefits of the 900’s increased interior size really started to shine. We were able to take the entire main hoop/halo assembly out of the car which made the welding far easier. Hassan spent the remainder of the day turning each joint from tack welds into fully penetrated, 360 degree welds. In the meantime, I decided some weight reduction was in order, so I grabbed the grinder and went to town.


The day grew into night, and we were all in agreeance that it was about time to wrap things up. We got much further than originally anticipated, and we used that momentum to shoot us forward into our hectic build schedule.

Stay tuned as we recap the 900’s journey to it’s first Chumpcar appearance in the next installment of the BGKP Saab 900 series.

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