Bay Area Miata Drivers
BAMD ArticlesBAMD Articles
Hard Dog Roll Bar Installation

by John Sloate

The manufacturer of the Hard Dog roll bar, Bethania Garages, provides written installation instructions with their roll bars, but they're somewhat lacking visually. So this is more of a picture record of an installation. The pictures are all from my '91 Miata. Later models will be similar, but some of the parts are different, so the areas to be cut won't be exactly the same. Still, this should give you some idea of what you're up against.

First, a little background. When I was young all I wanted to do was work on cars and drive cars, but as I got older and had a family there were other commitments that took up my time. So I quit working on cars and always tried to own fairly new cars that didnít need anything but regular oil changes. When I decided to buy my current (and first) Miata, I found one that had low mileage and was owned by a real car nerd.
Hard Dog M1 in a '91 Miata, with trim and carpeting removed.

roll bar
The guy used to remove the seats to vacuum the car. He had done a lot of upgrades to the car, and I felt the car was in good enough condition that it was almost like buying a new car. I figured I wouldnít have to work on it. So I bought the car and joined a Miata club. I started talking to people in the club and saw all the neat things they had done to their cars, and the urge came back to do a little car work again.

The previous owner had upgraded the suspension, added a supercharger, and installed several other go-fast goodies. He had wanted the car to look fairly stock, so he left the stock wheels and tires on the car, and did not add a roll bar. I wanted to be able to do track days, which I knew would require a roll bar.

So I started looking at roll bars on other Miatas and decided on the Hard Dog M1. A local shop wanted about $700.00 to install the bar. If you have the money and donít have the time, thatís a fair price because it requires roughly 20 man hours to do the install. However I have a lot more time than money now, so I decided to try the install myself. After BAMDís inaugural run in November of 2009, I was talking to Adam, another BAMD driver, and mentioned I was going to install the bar myself. He immediately volunteered to help. That was all I needed to get going.

I ordered the bar the next day and had it delivered to Adamís house. We decided to install the bar at Adamís because he has every tool we could possibly need, and then some. Adam had previously installed a double hoop roll bar in his own car, and he told me it took three days. But he felt between the two of us, we could probably do mine in one day. I ordered the bar direct from the manufacturer (Bethania Garage, and was told it would be delivered a week later. This was bad news because I was ready to get started. I downloaded the install instructions, printed all of the diagrams, and decided I could do some prep work so we'd be ready to go when the bar arrived.

I'm not going to repeat the installation instructions here because they're available on line from the manufacturer, along with a few diagrams. However, since I had never seen the areas of the car we would be working on, it took a while to determine from the diagrams exactly what I was looking at. So I thought actual photographs would have been more helpful, and that's what I'm providing here, photos to go with the instructions.

To prepare the car, the first thing I did was remove the plastic panels that cover the seat belt towers, and the carpet from the rear deck. The installation instructions said to just roll the carpet back, but I think it was easier to just get it out of the way. I put all the parts in zip lock bags and labeled the bags left and right side. I didnít realize how important this was, until I started to reinstall everything ten days later and I couldnít remember where everything went.

Adam suggested that I be at his house by 7:30 a.m. so we would have a full day to get the install done. We started by removing the fuel tank cover, which is the large aluminum piece that makes up most of the package shelf. This is very easy to accomplish, however, it does have a lot of bolts. Once that was removed we needed to determine where to make the cuts, so we referred to the instructions, which said, ďyou will need to trim the package shelf . . . as shown in FIG# HC1.Ē It took us a few minutes to figure that out, but we finally marked the area to be cut, and took pictures. This photo shows the area.

Adam used a Dremel tool with a cutting disc to make the cuts, smoothing out the edges with a sanding tube. After the cuts were made, the area looked like this:

Driverís side

Passenger side

At this point we moved the roll bar into the car. The bar is an extremely tight fit, and it takes two people to work the bar past the wiring. Once the roll bar was in place it was resting on a rubber pad, so we marked the roll bar's position and then cut out the area of the pad where the roll bar would sit. Also, there's a rubber knock out located on each side of the car where the roll bar will sit, and we had to remove these. The good news is, you can use this hole later to line up the backing pad under the car.

After the mat was cut out, there was some type of sealant that was used by the factory which we scraped off so that the mounting plate had a completely flat surface.

At this point we moved the roll bar into place and bolted the front of the roll bar support to the seat belt reel with bolts supplied by the manufacturer. The supplied bolts are longer than the original bolts.

We next jacked up the rear of the car and put jack stands under the frame, then removed the wheels and the plastic splash panels from the front of the inner fenders. The next step was to mount the backing plate to the upper rear brace foot plates. The first bolt was placed through the hole where the plug was removed. One of these holes lined up perfectly for the bolt, and the other one required only running a drill bit through it to open it enough to allow the bolt to go through. Here is a picture of the backing plate in place with the first bolt.

Once the backing plate is attached, you can use the plate as a guide to drill the two remaining holes on each backing plate.

Below the seat beat reel is a plate requiring three more bolts with another backing plate underneath the car. These three holes can be drilled from the inside of the car. After we had all the holes drilled and bolts fitted, we removed everything and applied Permatex around each bolt foot plate and backing plate to make sure we had a water tight seal. We let the silicone set up a little before tightening all the bolts.

We then tried fitting the fuel tank cover back into the car to estimate where it would need to be trimmed. After marking the areas to be cut, we again used the Dremel to cut out the notches for the roll bar.

The fuel tank cover was then bolted in, and the roll bar was officially installed.

The following day I installed the carpet, cutting out areas as needed for the rear roll bar braces, and installed the trim pieces. Cutting the trim pieces was the hardest part, because I was afraid I would really mess them up. But with a lot of patience I was able to get it done. As it turns out, most of the cuts are hidden when everything is finished. I like using the tonneau cover, which now doesnít fit because of the rear braces, however, I got an upholstery shop to modify the cover.

The installation wasn't as hard as I had anticipated, thanks mainly to the help of Adam, who did most of the work. For your own installation, having someone on hand who's done the job before would be very helpful.