Drum brakes have their place, in this author’s opinion, that place is on the rear end, if not in the trash. Drum brakes up front are just not safe. Sure, they technically get the job done, but many a scary moment has been attributed to stock front drums. A big problem is that disc brake swap kits cost a fortune, just a basic swap kit can cost $700, while the high-end upgrades cost a lot more. This is a lot of cash to put down for something as simple as brakes. These kits usually consist of spindles, brackets, shields, rotors, calipers and hoses. The basic conversion kits come with stock replacement-style components. This raises the question- “How much would the parts cost individually at the local parts store?” We set out to answer that question and we found the answer a little surprising.
With just a little (and we mean about 10 minutes) of extra work, we were able to convert a 1969 Camaro from stock front drum brakes to stock discs using brand new stock replacement parts for $321.47, including tax. We sourced all of our parts from the local parts store, all of which were in stock. We didn’t even have to wait for shipping.
There is a trick to this swap. All 1969-later GM drum spindles for cars that had a disc brake option were cast from the factory with a demarcation line on the upper backing plate mount. When a car was optioned for disc brakes, the top mount was machined down about 3\4 of an inch (this measurement can differ from spindle to spindle). This allows the caliper mount to sit square. This makes the low-buck swap easy, all you have to do is slice off the excess material and go.
Due to manufacturing tolerances, not all spindles require the same amount of trim. To make sure you cut off the right amount, bolt the caliper mount to the spindle and lay the upper portion against the caliper, then mark the spindle with a scribe. Using a die-grinder and a cut off wheel, the mounting boss can then be trimmed (carefully, and make sure it is square) and the rest of the swap completed.
The ’69-later spindles are threaded all the way through, so no tapping is required. This swap works on earlier spindles as well, but these spindles require drilling and tapping, still a cheap way to better braking.