An excerpt from: Secrets Magazine

I Found A Floater Back
Self Energizing Brakes
by Ralph Knopf, Highland IN

Did you ever wonder why the rear brakes on a Model 'A' seem to work better than the front? It's because they are actuated by a floating cam and shaft mechanism. The rear brake shoes expand when the camshaft rotates and the cam that connects the front end of the shoes and pushes them into the rotating drum. The upper, or primary, shoe picks up the rotation of the drum and forces the lower or, secondary, shoe into the drum. This floating cam allows the upper shoe to self energize the lower shoe, which multiplies the stopping power of the rear brake. The adjuster wedge at the rear of the backing plate acts as an anchor pin, and stops the rotating action of the shoes. This anchor pin is the part that absorbs the stopping power of the shoes. When the car is moving forward and the brake is applied, the upper shoe moves away from the adjuster wedge slightly. This is allowed by movement of the cam through the large hole in the camshaft. Note: that is why it is important to clean and lube this part when relining brakes.

How do we make the front brakes work as good as the rear? The front brakes operate by a wedge mechanism that just expands the lower end of the shoes into the turning drum. Unlike the rear brakes, the front shoes are anchored at the top (by the adjuster wedge) and at the bottom by the operating wedge. This does not allow any centrifugal movement of the shoes and no energizing occurs. So, we must find a good, simple and efficient way to "float" the front brake shoes. This will improve the system. The next time a modern iron cuts you off, or pulls out in front of you. You can hit the brakes with confidence and not run into the stupid idiot that doesn't like old cars.

During the last 15 years I have relined and done complete brake jobs on so many Model 'A's that I think I have seen every way there is to improve the Model 'A' brake system. I reline my own shoes with a molded lining that I put on in segments with tubular rivets. This lining is very durable and ventilates very well, stays cool and works very well with cast iron drums.

A problem that I had was that when the lining wore in, the pedal effort went up. The stopping power was good but the pedal effort was high. To remedy this I tried everything. I even tried the "floater" sold by Specialty Ford Parts. I feel this is not a floater but a toggle assembly. It worked, and pedal effort went down. Now, a different problem arose: the brakes began to squeal and then to howl. I could play a tune with my brake pedal. My wife said to me, "You're some brake expert. I'm embarrassed to ride in that car with you." That did it: I changed drums, I changed adjustment, I changed almost everything. It still howled.

My wife was reading Hemmings Motor News one day and said, "Look at this, an ad for brake floaters." I called the number and ordered a set. They arrived and I opened the package and found a true floater setup for the front actuating wedge (the Vintage Floater). I had seen this setup on a brake job I had done a year or so ago, but didn't realize the value of the part. I put it on my car and the howl and squeal were gone. Best of all, it stopped so good, I didn't want to stop driving. When I got back to the shop, I called and ordered ten more sets. I called my customers and we installed them on all the brake jobs I had recently done. Everyone is so pleased that I felt I had to share this information with the rest of the Model 'A'ers in the country.

The part that lets the front wedge float is the 'T' bolt that holds the wedge to the backing plate. The original 'T' bolt only lets the wedge move down to spread the shoes, and up to release them. The modified bolt lets the edge move up, down, and sideways. This connects the front and rear shoe making them self energizing and increasing the stopping power. The floating wedge in front works the same as the floating cam in the rear. The stopping power is increased and the pedal effort had decreased. You also get a better feel through the pedal of what the brakes are doing.