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Master cylinder sizes
clairetoo - 12/8/09 at 07:21 PM

I know this is a bit of a numpty question , and some one will be along in a minute to tell me to search - done that , cant find the answer
I am just working on the pedal box of a Fury with twin cylinders/bias bar , it has Wilwoods on the front and stock 9" drums on the back , and last time I drove it felt very `wooden` .
Both m/cylinders are .700 , and I have been supplied a .625 - but which should I fit it to - front or back ? (bearing in mind willwood billet dynalites on the front on 285 discs , 35mm pistons I think)
I have allso found the rear m/cylinder is seized solid - which may have accounted for the nasty feel to the brakes ?

[Edited on 12/8/09 by clairetoo]

theconrodkid - 12/8/09 at 07:26 PM

smaller dia will give more pressure but longer pedal travel

clairetoo - 12/8/09 at 07:37 PM

quote:
Originally posted by theconrodkid
smaller dia will give more pressure but longer pedal travel

Thats what I was thinking - the travel felt about right , but then the rear cylinder was solid , so the bias bar was just pivoting on that !
Allso both clevis`s had been screwed in , allmost touching the pedal - that dont look right to me ?

theconrodkid - 12/8/09 at 07:57 PM

you cant do a lot with the rear master seized? so replace that first and see how you go/stop delete as appropriate

adithorp - 12/8/09 at 08:07 PM

You need the smaller cylinder on the front brakes. Adjust the push rod in the clevis as listed in the tech bulletin on RallyDesign site. Make sure you have slight free play in the push rods otherwise the brakes will stick on.

http://www.rallydesign.co.uk/balancebar.php

adrian

MikeRJ - 12/8/09 at 08:42 PM

quote:
Originally posted by clairetoo
Allso both clevis`s had been screwed in , allmost touching the pedal - that dont look right to me ?


That sounds correct, they should be almost but not quite touching the tube that the spherical bearing slides within. This prevents the bar sliding left and right and randomly changing the bias and also limits the articulation of the bias bar. This means in the event of the failure of one circuit you can still apply pressure to the other, albeit with increased pedal travel.