[RocktimusPryme]

Originally Posted by Scarebird

Because of course they do - they sell them!

Almost all GM combination valves sold are made for one car: 1971 Chevelle with front disc/rear brake. It of course does not matter whether the master is manual or power - same pressure and flow in and out.

The OEM's no doubt expended quite a bit of time dialing in bore sizes of the master/front/rear for optimum braking under most situations encountered by day to day driving, so in reality no combo or delay valve is needed.



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I was just making the statement that a 4 wheel drum and 4 wheel disc setup are going to behave similarly. If all 4 wheels have the same configuration of brake, IMO you can pretty safely just be using the the factory jurassic era distribution blocks that came in most 4 wheel drum cars with lines just routed to the master cylinder as necessary. If a brake company is saying you can use the disc/disc combo valve for a drum/drum car. I feel like you can use the factory drum/drum block in a disc/disc car.

Im a little less certain when it comes to disc/drum setups, because its never been clear to me if the blocks that came in disc/drum cars from the factory are dumb hunks of metal, or if they have built in proportioning in them. Talking about GM engineering, I'm not sure what they engineered into the blocks in those cars. And maybe its not all the same, maybe some have proportioning built in and some don't.

Im not arguing, I agree with you that I would feel comfortable relying on the master to do what we need it to in most cases. Im just saying I don't feel comfortable stating you 100% for certain wont need some sort of proportioning device to the rear brakes when you switch from drum/drum to disc/drum. People should for sure listen to you over me, but I have done this a few times now and in different ways, and honestly, the brakes don't see to care very much how you do it. As long as they are getting hydraulic pressure from a pedal pressing a fluid filled cylinder, they do their job.