Installing Seatbelts in Older Cars

Driving around in a car with only lap belts, and lap belts which seem to have had 30 years of sunshine and wear taking their toll on them, is something I find unnerving. I decided to install a set of shoulder belts. I considered several alternatives, from bolting in a set of seats out of a Chrysler Sebring convertable (with belts that fasten to the back of the seat) to ordering a set of cheap shoulder belts out of a J.C. Whitney catalog. Since I'm quite a cheapskate, the latter idea won out.

When the seatbelts arrived, I was pleased to see that they looked almost exactly like the original lap belts would have looked like if they were new and set up as shoulder belts. The color looked great in my interior. The chrome buckles looked a lot closer to the original design than the aftermarket universal replacement belts Year One sells. Also, the buckle was designed so as to not slide loosely like on a modern seat belt, so even if I didn't find a satisfactory way of anchoring the top, they wouldn't be any more dangerous than the original lap belts. There was only one difficulty - getting them installed.

The first problem came when attaching the lap seat belt anchors to the floor. The seat belts in the Dart are anchored to the floor with two huge bolts, so big I had to use a lug wrench to get them off. Not surprisingly, they wouldn't fit through the holes drilled in the lower two seat belt anchors. This proved fairly easy to solve; I drilled out the holes so the bolts would fit. If you can find factory threaded holes in the floor pan to install seat belts in your car, it's a lot safer to reuse them than to drill new ones.

The second, and much more difficult, problem was how to anchor the top of the shoulder belt. The directions said to use the factory fittings, or if none were availible, drill a hole through a panel in a suitable location (check the directions that come with the seatbelt for just what constitutes a suitable location) with easy access to the back side, slide one of their reinforcing rings provided behind the panel, and run the bolt through the panel. Uh, right! How many panels in the inside of a car offer easy access to the back? The only one I could think of was the roof, and I wasn't about to drill holes in the roof and have bolts sticking through!

I considered several possibilities. The only clear place the belt could be attached to was the B-pillar. I thought about cutting a slit in the side of the B-pillar and using it to access the back, but that sounded difficult. Welding a plate with a threaded fitting to the B-pillar would have worked pretty well, but I don't have any welding equipment. I finally found the solution at the local hardware store.

The solution was a small clip [I'll post a picture of one soon] which was essentially a strip of sheet metal folded back on itself, with a threaded fixture on one surface and a theaded hole extending clear through both sides of the clip. A lip at the side opposite the bend enables the clip to be hammered through a slot in sheet metal so half the clip is on one side of the sheet metal and the other half is on the other. I bought two of these clips and went to work installing them.

Installing these clips is simple in theory, but difficult in practice. All you have to drill is a hole in the appropriate spot in the B-pillar large enough for the bolt that screws into the clip to pass through, then cut a wide enough slit next to the hole at a distance where the hole in the clip will line up with the hole in the B-pillar when the clip is hammered through the slot. The trouble is, the B-pillar on my Dart is made of very heavy gauge hardened steel, which makes it ideal for attaching seat belts solidly, but also makes it a pain to cut.

After about two hours, I'd finally managed to drill the holes and cut the slots. Be careful when cutting the slots, as if they don't line up correctly and you can't get the bolt to go through the hole after hammering the clip in, the only way to remove the clip is to cut it at the bend, letting half of it fall into the inside of the B-pillar, where it's next to impossible to remove. Fortunately, in this case, I had lined them up sucessfully, and the clips lined up fine when I hammered them in. The only thing remaining was to put the upper seat belt anchors over the clips and bolt them on.

Big Fat Legal Disclaimer: The only thing I can promise is that I actually use a setup like this in a car that I drive on a routine basis. Keep in mind, I also drove a car for two years without shoulder belts, so that's not guaranteeing much in the way of safety. I can't promise that a seatbelt installation like the one I've described will protect you in a crash. I think they'll give you a better chance than no seatbelts, but I'm really not quallified to say that with any degree of certainty, and there's still a chance of getting hurt even if they're as safe as any car without airbags. So in lawyer-speak, I assume no liability for any damages resulting from following the directions in this page, whether from correctly or incorrectly imitating what I did with my car!