Since our 1991 Toyota MR2 Turbo has proved so fun at track days and time trials, we felt that a proper safety upgrade was in order if we were going to do more of that.
Safety gear of any kind is that stuff you buy hoping you’ll never actually use it. Even when the supply chain wasn’t all messed up, you still couldn’t order a roll bar when you hopped the curb and have it delivered and installed before you hit the tire wall.
[Investing in your safety setup? Take inspiration from FCP Euro’s IMSA effort]
We installed an Autopower bolt-in roll bar into our MR2. We lay out how we did it below, and most four-point bars should follow a similar process. How much to get a bar like this? Retail is $895, and ours features 1.75-inch tubing.
First you need a car, and you need to make space in the interior. For our Toyota MR2, removing the T-tops offered an amazing luxury: a lot more room to move around. The next real step involves removing all of the interior bits that prevent you from sliding the bar into the car and attaching the feet to bare metal.
In our MR2, we had to remove both seats and the rear firewall’s carpeted liner. Each seat is held in with four bolts, but the driver’s seat has one bolt hidden behind the controls for the trunk lid and fuel door. A slotted screw and Phillips screw hold this lever bracket to the car.
The rear carpeted liner is held in mostly by push-style fasteners. To access them, you’ll need to remove the center console, the optional CD storage console, the trim under the rear window, and the trim covering the seatbelt reels. The lower window trim is secured with two screws, one located under each coat hook (or coat hook block-off plate) and several push clips. The side trim snaps in withspring clips.
The only thing that rivals Autopower’s ability to protect you when driving the car is the company’s ability to protect its bars in shipping. Unwrapping the bar without scratching it is an exercise in patience, and there’s about a 138% chance you’ll slice through the hardware package, sending bolts and nuts everywhere. Take your time, though, and you’ll be rewarded.
Once the bar is out of the packaging, make sure you have all the hardware. Check for any damage that may have occurred during shipping, too, particularly to the foot plates.
Now you can slide the bar in the car for a test fit. We left the carpet in place since it was thin and we wanted to trim the carpet around the feet as closely as we could. If you have particularly thick carpet, you may need to trim it in advance to create enough room. Autopower bars are built to use every available millimeter of clearance and frequently have tight fits right to the headliner or other interior trim.
The rear foot plates match a contour in the rear bulkhead, so the bar pretty much snaps into place once in the correct position. With the bar in place, we marked the carpet so we could trim around the foot plates.
Once the carpet is trimmed and you’re able to get solid metal-on-metal contact with all four contact points, it’s time to drill, baby, drill. We like starting with one hole for each foot plate; we’ll drop a bolt into each hole as we drill it to keep the bar steady before moving on to the others, drilling one at a time.
And a note about drilling: Before you begin drilling for any roll bar or cage, know what’s behind that panel. Autopower does a great job of finding nice, open spaces for attaching the support plates, but occasionally you’ll still need to clear the other side of the panel before you drill. If you drill a hole in your car and sparks or fluid come out, you’ve made a horrible mistake. This would also be a bad time to drill through your own hand.
[So You've Drilled Through Your Own Hand]
In our MR2, both foot plates were completely clear on the opposite side. The driver-side firewall brace was wide open in our car, but MR2 owners with stock airboxes might want to first remove them. On the passenger side, the intake tube going down to the intercooler could be in the danger zone if you’re using a long drill bit.
Once you’re through, a punch or long screwdriver can help you locate the actual hole. On most cars, you’ll be drilling these holes for the rear supports in the rear floor or wheel wells, so access for the backing plates will be easy. With the MR2, we were drilling into the engine compartment, so access was much trickier.
On the driver side, once we had that first hole drilled and a screwdriver stuck through it, we could see how much insulation material we had to cut back to get a metal-on-metal connection with the backing plate.
On the passenger side, a friendly rodent–likely knowing we would eventually be installing a roll bar–took care of trimming back the insulation.
In that picture of the passenger side, you can also see the structural bulkhead support that would theoretically interfere with the upper-left (when viewed from behind) bolt. There’s a similar bulkhead brace on the driver side as well.
Because of these structural braces, some trimming of the backup plates is needed. A cutoff wheel makes quick work of the excess material and gets your plates ready for install.
Once your holes are drilled, it’s time to start bolting. The Autopower kit comes with appropriate-length 3/8-16 bolts and an adequate supply of nuts, but we recommend having some longer bolts, or even some pieces of threaded rod, on hand for the initial install.
Ultimately, you want a perfectly flat sandwich composed of the foot plate, then the car’s sheet metal, then the backup plate.
However, frequently the panel is not perfectly flat–or it’s double-walled or has some other configuration that prevents a perfectly flat junction without some smooshing. Running some longer bolts or threaded rod through the holes for that initial tightening can help accomplish a nice, flat smoosh. Then you can remove your temporary fasteners one by one, replacing them with the supplied hardware.
The finishing touch is applying double nuts (we also applied a dab of chemical thread-locker) to all your bolts. The supplied hardware is perfectly sized to accommodate the foot plate, backup plate and properly flattened sheet metal. If you come up short somewhere, you might want to take a second look to see if you did enough smooshing. And remember to install SFI-approved roll bar padding anywhere you may have potential contact with your rollover structure. Next we'll upgrade our seat and driver restraints.
Wrapping the sub belt around the front of the seat like that goes against everything I've ever been taught about how to install a sub belt. Not to mention the little blurb in the very article you link to regarding that topic: "Sub-strap must not be routed around the front of the seat."
The use of a reclining OEM seat with a 5 point harness and roll bar scares me.
Shouldn't it be a 6 point so you can wrap it around where the lap belts come out, effectively sitting on the anti-sub points?
Not to mention that the reclining feature will be the first to go in a roll over incident.
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