This is my new pedal box setup from CompBrake it's the first one made for a Sierra.
With it came two master cylinders marked up 0.7 and 0.625 but in fact both once out the box was infact two 0.7's

Now i've tried Googling the answer as to the best setup for Master Cylinder size but their are wildly differing claims to the best setup, some saying larger size on the rear some saying larger size up front and of course some giving answers in metric and some in imperial.

I would have thought you'd want a larger cylinder upfront as i'm tring to move 12 pots in total on the front and just 2 at the rear and I obviously want a front bias brake setup.

Happy to be proved wrong just want to make sure it feels right and more importantly stops the car lol.

Cheers Rich

 

Any thoughts anyone?
Cheers Rich

 

Surely you want a bigger one up front or else with more braking to the rear when you brake on a bend it's going to be like yanking on the handbrake

 

i was told to use the 625 up front and the 7 on the rears as the rears will then have less braking

obviously the best peeps to ask would be the likes of mr airtec, ronnie amis, or mr brakes, martoon as they can offer real life real world experience of doing what you are trying to do

i had this set up on my 3 door and, to be honest, i wasn't impressed by the amount of pedal effort and after searching ages for a servo boost set up it was all just trouble as no one back then did an off the shelf item for a turbo'd engine

 

Smaller cylinder to the front normally.

Try sucking fluid through a straw, then
try sucking it through a drainpipe, same
principle. A small cylinder will apply more
Pressure for the same given effort.

 

I use a .625 for the front brakes and .7 for the rear. This is because for equal pedal travel and pedal pressure you'll get a greater braking force from a smaller cylinder.

Charlie