Would this brake conversion work?

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Schyrjajew

Schyrjajew

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Hello, everybody.

I have a 65 Valiant SW 273. It has 9 inch drum brakes and a brake booster.
I would like to convert it to a dual-circuit brake system.
I already had a 68 with a dual-circuit system some time ago, but without a booster.
Is it possible to use the same wheel brake cylinders and master brake cylinder as on the 68? Or do the 68er not fit on the anchor plate?
Do I need a different booster or can I keep the 65?

The 65 has the following original wheel brake cylinders:

Rear: Bore 13/16,
Front: Bore 1
Port size ???

And the 68:

Rear: Bore 13/16
Front: Bore 1
Port size 3/8-24

So I'd install everything just like the 68. Brake lines and distributor cross would then be new (the same as on the 68).

I don't want disc brakes, by the way
 
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You will get very negligible or not at all change from changing the wheel cylinders, IMO. I would just upgrade to the dual reservoir master cylinder and be done with it. I have one for my 64 but my lazy butt hasn't done it yet.
 
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RustyRatRod said:
You will get very negligible or not at all change from changing the wheel cylinders, IMO. I would just upgrade to the dual reservoir master cylinder and be d one with it. I have one for my 64 but my lazy butt hasn't done it yet.
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Just for information: I have to change everything on the brakes anyway. The car stood 20 years
 
I would keep the stock wheel cylinder sizes, but I like the adjustable prop valves better than the stock setup. Just run your new brake lines directly to the front brakes and put the prop valve inline to the rears. Done it on a couple cars and it works great.
 
Schyrjajew said:
Just for information: I have to change everything on the brakes anyway. The car stood 20 years
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Unless you change to the larger brake shoes, 1) I am not sure the larger cylinders will FIT and 2) you will see very little difference. I bought my 64 Valiant in January that had sat since 1982. That was the first thing I did after I got the engine running was rebuild the brakes. Mine has the 9" drums all around and it stops very well.
 
jas0162 said:
I would keep the stock wheel cylinder sizes, but I like the adjustable prop valves better than the stock setup. Just run your new brake lines directly to the front brakes and put the prop valve inline to the rears. Done it on a couple cars and it works great.
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A proportioning valve is for a disc brake system. He does not and will not need one. All he needs to run the dual master cylinder setup is the dual master cylinder, a new distribution block and he adds two lines. That's it.
 
RustyRatRod said:
A proportioning valve is for a disc brake system. He does not and will not need one. All he needs to run the dual master cylinder setup is the dual master cylinder, a new distribution block and he adds two lines. That's it.
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Thanks, and what about the brake booster?
Right now there is the normal one in, Bendix I guess...
 
Schyrjajew said:
Thanks, and what about the brake booster?
Right now there is the normal one in, Bendix I guess...
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It has power brakes now? THen just make sure you get the 67 MC for power drum brakes. Otherwise, I wouldn't add power. These cars are light as a feather.
 
RustyRatRod said:
It has power brakes now? THen just make sure you get the 67 MC for power drum brakes. Otherwise, I wouldn't add power. These cars are light as a feather.
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Yes it has power brakes and the fact is that I am not sure if this original brake booster works with dual MC or if this doesnt mater. :) i don't really want to buy a new Brakebooster ;)
 
Schyrjajew said:
Yes it has power brakes and the fact is that I am not sure if this original brake booster works with dual MC or if this doesnt mater. :) i don't really want to buy a new Brakebooster ;)
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I don't see where it will make a difference. Doesn't the MC have a four hole flange?
 
RustyRatRod said:
I don't see where it will make a difference. Doesn't the MC have a four hole flange?
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Yes, but I thought maybe you still have to change something, because it is actually meant for a single circle. You probably know better...

But if it's no problem i will buy a 67 MC, distribution Valve and add 2 lines.
 
Schyrjajew said:
Yes, but I thought maybe you still have to change something, because it is actually meant for a single circle. You probably know better...

But if it's no problem i will buy a 67 MC, distribution Valve and add 2 lines.
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Single circle? Say what? I believe all you need is the 67 MC for power drums and the distribution block and just add the two lines. That should be all.
 
I think an all drum car can benefit from a prop valve the same as a disk brake car. Lots of Drum cars came with them from the factory. The front and rear axle have different brake shoes, different weight load, different wheel cylinder sizes. A prop valve may not be needed but they can help you fine tune your system and make your car safer.
 
I'm kind of going thru this with my 65 barracuda. Unless you are going for originality etc etc I would go back to a simple manual brake system. Your call on dual or single circuit. Because of issues when i received the car I went back to manual brakes and they work fine. I did a single circuit to be able to use the car but will upgrade to a dual later. Bottom line - manual brakes are fine for these cars.
 
rkjjeep said:
I'm kind of going thru this with my 65 barracuda. Unless you are going for originality etc etc I would go back to a simple manual brake system. Your call on dual or single circuit. Because of issues when i received the car I went back to manual brakes and they work fine. I did a single circuit to be able to use the car but will upgrade to a dual later. Bottom line - manual brakes are fine for these cars.
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Alright, thanks guys. I'll give you a feedback how I did it etc.
 
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