Hey guys . I need some advice on what brakes are easy to put on the stock rear axle on my 1931 Model a coupe . I got 42-48 spindles to use up front , also have 1956 F100 brakes . So what is the normal to use on the rear ? Thanks in advance
I'm guessing you have mechanical brakes on the rear? I would go with '39 & later hydraulics.What brakes are you using on the front ? master cyl. ?Is the car plumbed for hyd.brakes?
Now it has the stock mechanical brakes . Will the 39& later rear brakes bolt to the rear axle ? How is the emergency brakes on the 39& later ? I dont have a master cyl yet , is there an adapter to use the stock pedal ? I am trying to keep it old style .
On a '37 sedan We did a few years ago The shop obtained a conversion kit from Richard Lacy. The m/c was a two compartment unit from '39 & later Ford.The E-brake is cable operated. I don't know if the '39 backing plates will fit the Model A diff. I'm sure someone on here knows. Richard Lacy can be reached online: earlyv8garage.net or (626)338-2282
39 - 48 backing plates bolt right on the Mode A axle. When installed as stock with wheel cyl on top you will have contact with the A spring perch. Some cut to get rid of contact. Myself I change backing plates side to side and turn 180* and mount it with wheel cyl. on the bottom. Then the E-Brake cable comes out facing forward as it should only on the top of baking plate. Some will call B.S. but it works and the brakes don't have a clue things are on up side down. Make sure you put the front shoe on the front side and the rear shoe on the rear and you'll be just fine. You may need to add a shim on the tapper of the axle to keep the drum form dragging on the backing plate but several Model A parts suppliers have them in stock. It's not a big deal.
Here is some info. Many ways to do the rears. Pistn-Brokes is a good one. https://www.jalopyjournal.com/forum...ting-39-48-hydraulic-brakes-to-your-a.124112/ 4648brakes.html John
Don't forget that you'll need to turn the wheel cylinders over so that the bleeder is at the top, otherwise you'll not be able to bleed them properly. This is most easily done by enlarging the center hole upward until the wheel cylinder bolt holes line up with the existing backing plate holes with the wheel cylinder inverted. This can be done with a die grinder.
Several ways to get it done. I believe in K.I.S.S. Here is the backing plate mounted wrong according to some. Trust me, the car don't know it. Stock A pedals and the 39-48 master mounted. Look close and you'll see I change it just a bit. Home made bell crank to make things work. Now notice the Master has spacers between it and crossmember. That's so I can get to the cap with the body on the chassis. Also notice where the brake lines go on the rear end. It isn't Rocket Science. Buy a Kit? You don't need no stinking Kit.
I know it sounds like I don't know what I'm doing but I can tell you I don't do all that and things are just fine. Just be sure you have front puck facing forward. This chassis has been together about 15 years now and the brakes just keep doing there job.
I did it just as if the bleeder was at the top. So my wild guess as to why it works is that the master will move more fluid than the bleeder can let out and will purge the wheel cyl. with fluid causing the air that is less dense than the fluid looking for a place to go. With the dense fluid squeezing and pushing the air it follows the fluid movement and ends up coming out the bleeder hole. Now that's an uneducated guess and for sure not scientific at all but all I can come up with as to why it works and I end up with a good solid pedal. If I had only done this once I would say just plain dumb luck but I have done this system 4 times for myself and twice for friends. Each time it ends up the same. How can that be?
As long as the bleeder is at the top of the bottom air will rise to it.If the bleeder was at the bottom of its new location air could get trapped.
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