Brake experts...is this right?

[absintheisfun]

I have been looking and looking, and just when I think I get an answer, it gets completely changed on me...which one of these below is correct, or if none of the above, please let me know!



https://static1.pt-content.com/images/pt/2010/09/brakes-1.png

[wmhjr]

Assuming 4 wheel discs, none are correct.

Correct would be drawing A but with prop valve inserted between master cylinder and rear T.

[formula]

Think it through: you want the same line pressure for the brakes on each axle, so you're going to want a T on each axle to ensure that the front two are even and the rear two are even. The proportioning valve decreases line pressure beyond it, which is what you need to make sure that your fronts lock up before your backs by decreasing the pressure the backs see--so you're going to want a prop valve on the back line.

Dunno who told you those three--but whoever it was, don't let them work on your brakes! jeeze!

--A would have the same line pressure front and rear, almost guaranteeing that your backs would lock first and making the car very unstable

--B would make equalizing the pressure between the front two almost impossible, and still put too much pressure to the rear.

--C....is nonsense?

[absintheisfun]

Yup, 4 wheel disc. So this is the correct way to route the lines?
https://static1.pt-content.com/images/pt/2010/09/brakes1-1.png

[wmhjr]

Yes

[Apogee]

And not to read too much into your schematic, however don't assume that the forward port on the master cylinder goes to the front brakes and visa versa. Some master cylinders like Wilwood, C3 Corvette, etc are plumbed that way while others are not.

Tobin
KORE3

[MCB Matt]

Keep in mind, running both front and rear feeds from the master thru a prop valve is the safest way to do it and if the car is 67 or newer technically you must legally do it this way because of the dash "brake" warning light and the fact the valve will close off fluid flow to the side that looses pressure! You can then run the rear feed thru an adj valve to set the bias to your liking.

Matt