Drum/Drum master cylinder. Front/rear - should I care?

[GranTorinoSport]

On my 66 300 one thing I have done during my hard brake pedal fiasco is convert to a dual drum/drum master. Got the distro block and plumbed it up.

The question arose, for drum/drum master (67 C body master) does it matter which port I use for front and which one for rear? I think right now I have front feeding from and rear feeding rear.

 

[stubs300]

Got the distro block and plumbed it up. I think right now I have front feeding from and rear feeding rear. The question arose, for drum/drum master (67 C body master) does it matter which port I use for front and which one for rear? I think right now I have front feeding from and rear feeding rear.

With a drum/drum setup, you don't need this part, remove it! You think? If you don't know, I'd worry and not drive the car till it's fixed. Front feeds rear, rear feeds front! Good Luck

 

[GranTorinoSport]

With a drum/drum setup, you don't need this part, remove it! You think? If you don't know, I'd worry and not drive the car till it's fixed. Front feeds rear, rear feeds front! Good Luck

the block is just a distribution block not a proportioning valve. There was one there originally for the single master setup and this is just the InLineTube version for upgrade to dual master so I’m not worried about the block. Just wondering if reversing the front/rear ports on a drum/drum master actually makes any difference. I’m familiar with why you’d never want to do that on a disc/drum master, but on drum/drum does it make a difference and if so, why?

 

[PH27L7]

The pressure exiting the MC will be identical so there will be no performance impact on a drum brake car with no proportioning valve.

 

[stubs300]

Just wondering if reversing the front/rear ports on a drum/drum master actually makes any difference. I’m familiar with why you’d never want to do that on a disc/drum master, but on drum/drum does it make a difference and if so, why?

The bigger bowl supplies a larger area to get to the rears where the back reservoir[smaller bowl] is closer to the front and doesn't need to be as big.

 

[PH27L7]

The bigger bowl supplies a larger area to get to the rears where the back reservoir[smaller bowl] is closer to the front and doesn't need to be as big.

Drum brake M/C's are equal volume front & rear.

 

[stubs300]

Never mind!

 

[Big_John]

On my 66 300 one thing I have done during my hard brake pedal fiasco is convert to a dual drum/drum master. Got the distro block and plumbed it up.

The question arose, for drum/drum master (67 C body master) does it matter which port I use for front and which one for rear? I think right now I have front feeding from and rear feeding rear.

I'd do it the way the factory designed it. Here's a video about how it all works.

 

[PH27L7]

I'd do it the way the factory designed it. Here's a video about how it all works.

Good info! I agree, change it to the correct front/ rear orientation.

 

[65sporty]

I'd do it the way the factory designed it. Here's a video about how it all works.

I am in the process of swapping out to a dual master on the Sport Fury and I thought I knew which ports are the front and rear. This video confirms it and also told me why.
Thanks John

 

[GranTorinoSport]

That was a great and informative video.

it seemed to hint toward the end that gravity bleeding a drum/drum master was not a good idea due to the residual ports in the MC? I have been gravity bleeding my system a few times. Should I stop that and do the pump method?

 

[65sporty]

That was a great and informative video.

it seemed to hint toward the end that gravity bleeding a drum/drum master was not a good idea due to the residual ports in the MC? I have been gravity bleeding my system a few times. Should I stop that and do the pump method?

Bench bleed the master then install it. You can let it gravity bleed, but I would always finish by having someone pump and hold the pedal while I bleed each wheel.