[DeTomaso] Brake question

[Rob Dumoulin]

When i got the car it would not hold pressure and there was no parking
brake cable. The shuttle valve was cracked. I removed it totally and
replaced the massive proportioning monstrosity with a modern adjustable
one. I also added two pressure gauges up front thinking i might meed to
fine tune the bias. I never did get it to lock up and leave it wide open.
Girling calipers are stock.
On May 12, 2012 1:18 PM, <MikeLDrew at aol.com> wrote:

>
> In a message dated 5/12/12 9 46 16, guson at home.se writes:
>
>
> Removing the shuttle valve will not affect brake performance at all, right?
> The prop valve is different.
>
>
> Ah, my mistake--I was confusing the two!
>
> Removing the shuttle valve will not affect brake performance as long as
> the system is replumbed so that the front and rear systems are separate and
> independent, and so long as the stock front pressure reduction valve
> remains in place.
>
> If the shuttle valve block is kept in place and simply is gutted by
> removing the internals, then you have really screwed up your brakes,
> because now the front and rear systems are connected.  Any differential
> pressure created by the reduction valve will be offset by the fact that the
> systems are connected downstream.  The result would be excessive front
> braking/reduced rear braking (same as if you removed the pressure reduction
> valve), and also an elimination of any safety because now a failure in one
> circuit will affect the other one.
>
> If the systems are mixed this way, then a dragging brake caliper that
> heats up the fluid, would eventually heat the fluid to the other three
> calipers.  Doom.
>
> Rob--tell us exactly what you've got going on plumbing-wise?
>
> Mike