I've never worked on discs before, and I've got a couple of questions that are probably pretty basic. I'm using a caliper adapter similiar to that sold by Plydo & Fatman that bolts to the backside of the spindle ***embly. My spindle ***embly is the same as that used on about a zillion Dodge trucks all the way into the post-war era I believe. Calipers are early '80's GM truck, pads are early 80's Camaro, etc., and rotors are 76-80 Volare. Now my questions: 1. When I go to install the caliper there is not enough room for the pads. The inboard pad is hard up against the face of the rotor. I don't know how much room I'm supposed to have between pad and caliper, but I can't even get the loaded caliper into its place. It appears that the distance from the inner face of the rotor to the caliper mounting bracket is different at each of the four mounting bolts, and particularly tight at the upper, forward mounting bolt. I think I could get clearance by putting a washer on that mounting bolt between the spindle ***embly and the caliper mounting (adapter) bracket, but I wasn't sure if that was kosher, and I'm not sure how far out of parallel is acceptible for the caliper -to- rotor relationship. 2. I've got the calipers on the correct sides per the Napa part numbers, and the castings actually have R and L cast right into them, but in the position the bleeder is not at the top. It appears that by switching sides with the calipers it would solve the bleeder problem, but it seems sort of odd... I'm attaching a couple of photos that may or may not help you visualise whats going on.
Are you sure the caliper bracket isn't suppose to sit in front of the spindle instead of behind it like you have it bolted up now? If you move the bracket to the front, the off set in the bracket will kick towards the motor more and your calipers will have the bleader screws on top like they are suppose to be? I did the disc brake conversion on my son's 47 a couple years ago, but I think the calipers were in front of the spindles, but that WAS a long time ago. Gene
Sorry for the big pics, I didn't have time to resize. PlyDo sez it's kits for 34-41 Mopars uses various "GM auto" make/model calipers and rotors on the stock spindles and bearing. The spindles require some light machining. But thats for cars. They don't show trucks in the catalog. They list the Chrysler Corp rotors as being for the 46-54 Mopars....?? PlyDo kits for later 40's/early 50's have rear mounted calipers, as below. (I don't have any pics of earlier suspensions) Tom at PlyDo is the guy with the right answer
The bracket was in the right place in front of the axel. It turned out the problem was limited to one side, and was caused by the inner face of the spindle (where the adapter bolts up to it) not all being in the same plane. It was just built into the original forging from the factory. I solved the problem by putting a washer between the caliper adapter and the spindle to make the bracket (and therefore the caliper) sit parallel to the rotor. Now that's my idea of technology! That still doesn't explain why the rotors need to be swapped left for right to get the bleeders to the top, but I guess that doesn't matter? One other question (I did say I haven't done discs before, right?): The calipers come with 4 rubber bushings- 2 small and 2 bigger- that go on the caliper mounting bolts. My Chiltons even shows them, but doesn't show where exactly they belong. Where in the caliper/pad stack do they go?
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