Brake conversion issue

I have searched and found many issues but none like mine. The subject is a 57 Chevy 210 with power disc on front.
When driving normally all seems well. Brakes stop the car.
In an aggressive stop the first 1/2 of the pedal travel feels good but the second 1/2 does not seem to make it brake any harder and the right rear locks up.

I have adjusted the rears thinking that they are stopping the from from doing its job but with a dual master, this should not be the case

What do I need to check?

 

Have you installed the hold off valve?

 

The left rear cylinder may be stuck. Rebuild the rear cylinders using the same parts, its free. Check the bores for grime, use sandpaper if nessesarry.

 

Does the car nose dive?

Weight transfer to the front during hard stops will lift the rear. This can cause the rear brakes to lock.

 

Does not nose dive. Rebuilding rear wheel cyl is good idea and while I am at it I think I will replace the springs and such. Just because they are old and new ones are low buck. As for hold off valve. Not sure what that is and since I bought the car this way please tell me where to look. THANKS TO ALL


Posted from the TJJ App for iPhone & iPad

 

Make sure your M/C piston is atleast 1 inch...

 

If your rears lock up before the fronts you may want to look at an adjustable proportioning valve.

 

Have you had the wheel off yet? The one that locks up? It could be the wheel cyl. is leaking or a bad axle seal, contaminated the shoes and will cause the wheel to lock up. Just a thought.

 

It is clean with no leaks.


Posted from the TJJ App for iPhone & iPad

 

You didn't say what rear you have is it stock? Stock wheel cyl size? I second the adjustable Prop valve if everything else is in proper working order.
Let us know what you find.

 

rebuild it anyways