In the ‘60s we installed an Air Force surplus lap belt in Tom McMullen’s ’32 roadster so that we could compete at the drag strips and dry lakes, but they remained beneath the seat cushion the rest of the time. When we did the major rebuild of the roadster, adding the big 427 Ford engine in 1967 for the Popular Hot Rodding Magazine articles, we did add a set of lap belts.
By the ‘70s seat belts were now mandatory equipment on all vehicles and used by many drivers, though still resisted by some even after the failed attempt to make use mandatory in the late ‘60s by wiring the belt’s buckle to an ignition disconnect system. The vehicle wouldn’t start unless the driver’s seat belt was buckled. Some people buckled the belt and then sat on it.
I was one of the diehard fools that resisted using seat belts until the mid ‘80s when, while discussing racing with 3-time World Driving Champion Jackie Stewart, he pointed out that seat belts not only protected you from injury, but keep you firmly in place to regain control of the vehicle after the first impact of a crash. This allows you to avoid additional impact with other objects because the first impact is not usually with that famous “immovable” object.
Three-point seat belts are the most effective in your everyday “driver” but are not easy to install in my open roadster. So I had to install a set of lap belts in it because I no longer drive anything but a motorcycle without them.
To install them I followed the instructions included with the set. First consideration was with the anchorages. All US passenger cars, beginning with the 1962 models, have seat belt anchorages for at least two lap belts in the front seat. Since January 1, 1968, vehicle manufacturers have been required to install lap belt anchorages for each front and rear seating position and upper torso belt anchorages at each forward facing outboard seating position. On January 1, 1972, this same requirement became effective for trucks.
Where the manufacturer has made special provisions to attach belts, be sure to use those fittings. When you use the manufacturer’s threaded floor fittings, it is important that all full-threads be engaged to obtain the ultimate strength of the anchorage.
Seat belts should not be attached to the seat, unless the vehicle manufacturer indicates that the seats and seat mounting systems have been specially designed to withstand seat belt assembly loads.
However, for vehicles produced prior to 1962, anchorages have to be created. There are excellent and inexpensive kits available for doing this from companies like Juliano’s, but I chose to make my own mounts and weld them to a combination floor support and rear seat channel mount.