<VV> Dual or Single Master Cylinder

[JVHRoberts at aol.com]

My issue with the original dual master cylinders has to do with the safety  
factor. Blow a circuit, and you really don't have much left. The pedal goes  
nearly to the floor, and and you have VERY little braking action left. If the  
forward circuit in the cylinder blows, you can pump the brakes and get the 
other  one to work. If the rearward circuit blows, you're hosed. 
Anyone ever had any experiences putting in dual master cylinders from much  
more recent cars? I know the ones in our Subarus and my Z work well with one  
blown circuit. (bleeding is my experience) The one in my Fiero GT still has the 
 same problem as the Corvair dual cylinder... Arrrgggh...
 
John
 
 
In a message dated 12/4/2005 1:57:08 P.M. Eastern Standard Time,  
Sethracer at aol.com writes:

I have  a  single replacement master cylinder for the brake system on my '64. 
 
Is a dual  really necessary for safety or any other  reasons?

Bob Vukas
_bowtieguy at cox.net_ (mailto:bowtieguy at cox.net)  





I am bringing this up again (does that make me a  redundant  system?) the 
earlies have one additional reason to use a  dual system. A rare  failure 
mode on 
an early, is the failure in the  axle assembly  attachment that allows the 
axle 
assembly  (wheel/axle/brake  drum),  to move out from it's mounting - as in  
out 
of the wheel well.  It has to do with the U-joint/ yoke  attachment, and the 
axle bearing fit. It is  rare but it happens. If  that happens on a single 
master cylinder set-up,  you lose not only  your hydraulic braking at all 
four 
wheels, but your emergency   braking as well, since one drum has departed. 
Engine 
compression will not  have  much effect either, since one side of the 
differential is in  free wheel. if you  are going through the complete system 
and do not  
mind the non-stock appearance  of the dual master, think about adding  this 
safety system. If the above scenario  did happen, you would  still have front 
braking. -  Seth