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Brake pressure limiting whatsit
flak monkey - 18/7/06 at 11:33 AM

I have cortina discs up front and sierra drums up back.

Will I need the decelleration valve whatsit in the rear brake line?

David

Confused but excited. - 18/7/06 at 11:44 AM

Someone hurry up and answer him.

I plan to use the same bits and I've never heard of a decelleration valve whatsit.

So guys: DO WE NEED ONE?

andyharding - 18/7/06 at 11:45 AM

No

mookaloid - 18/7/06 at 12:01 PM

Should be fine without but can be fitted later if really necessary

Confused but excited. - 18/7/06 at 12:12 PM

Cheers Andy !

Thank you Mookaloid.

[Edited on 18/7/06 by Confused but excited.]
Cheers JoelP.

[Edited on 18/7/06 by Confused but excited.]

JoelP - 18/7/06 at 12:12 PM

never use the deacceleration valve, if you decide you have too much rear breaking you need to fit a pressure reducing valve or similar, the deacceleration device is linked to braking force and the angle its installed at, im sure it works fine on a sierra but thats what its designed for.

Dick Axtell - 20/7/06 at 09:08 PM

quote:
Originally posted by JoelP
never use the deacceleration valve,...device is linked to braking force and the angle its installed at, im sure it works fine on a sierra but thats what its designed for.

Bloody hell YES!!
I worked on these things, and from the producers point of view, they are wonderful! That's because no-one ever knows if they ever fail (until it's too late!). Try to figure out how to test them on the vehicle.
And.....?????
That is why I urge you guys NOT to use these things. They can be beaten, under emergency braking conditions (which is why we had to make them flow-sensitive, as well as decel- conscious).
use either those Fiat valves, or the Fiesta screw-in valve.

Good hunting round the scrappers!

Mark Allanson - 20/7/06 at 09:33 PM

With drums at the rear, you are not going to need one.

But if you really want one, fit rear discs then reduce their efficiency to that of drums with a fiat type reducer

robertst - 20/7/06 at 10:59 PM

quote:
Originally posted by Dick Axtell
I worked on these things, and from the producers point of view, they are wonderful! That's because no-one ever knows if they ever fail (until it's too late!). Try to figure out how to test them on the vehicle.


thats like saying the same with airbags... how do you know if they work? and what about ESP? the fuel cutoff switch in case of severe accident? what about the roll-over bar? and the collapsible steering column? how do you know THAT works when you got it from a rusty old dodgy donor sierra?

i could go on and on and on... if you have it and its there... hell just put it on. its not going to increase braking force! the most it can do is fail and then you are back to sqaure one... no brake deceleration valve and standard braking...

but what if it does work?

i mean come on... i'm having a tough time convincing myself on not using the brake servo and trashing it...

[Edited on 20/7/06 by robertst]

rusty nuts - 21/7/06 at 04:06 PM

At least with the fuel cut off you can give it a thump , if the pump stops the switch is working.

BKLOCO - 21/7/06 at 06:31 PM

Well I've fitted it.