Hejj all,

Ok,

I'm having some problems with my brakes.
The pedal is hard real quickly, but they don't stop the car verry good.
Looks like the front isn't doing verry much.
Setup is cosworth 2wd callipers and disks (283) at the front with braided hoses en xr4 calipers and disks (253) at the rear.

Already changed all the pipework @ the front, reconditioned the front calipers, changed the brakeassist, changed the master brake cilinder but stil brakes like crap.

Anyone got any advice?

thanks.

 

What size is the master cylinder ?

 

as above and have u bled the system through properly

 

Have you checked the brake servo is functioning ok?

 

Size of the master cilinder is standard rs turbo one.
Should i upgrade to a bigger one?
I thought the standard one would do fine but i would just have to push it a little further down.
Problem now is it get's hard pretty fast and i can push as hard as i can but it doesn't really stop verry fast.

 

In my opinnion i have... if it's not been bled properly it would be real soft pushing the pedal to the floor easy wouldn't it?

 

Haven't really checked it , did replace it for another one with the same effect.
How can i check it for working properly?



Thanks all sofar

 

Did you bleed the ABS pumps ?

What pads (make and compound) are you running ?

Tony

 

Sounds to me like there is no servo assistance working.

Check the vacuum pipe from the inlet manifold to the brake servo for splits, one way valve working etc.

also check the diaphragm inside the servo is not split.

 

As above check the vac line between the intake manifold and servo for splits etc. The one way valve is only there to prevent positive pressure entering the servo when on boost. However if this valve has stuck in the closed position then it will prevent vaccuum from reaching the servo.

The way to test the servo is - Engine off, pump the brake pedal a few times to depleat the vacuum from the servo (the brake pedal should now be solid if not there may be air in the hydraulic system somewhere). Hold your foot on the brake pedal and start the engine, the pedal should sink as vacuum builds up inside the servo.

 

Haven't got ABS anymore.

Pads are standard cosworth at the front and standard sierra at the rear

 

I've noticed no splits in the vaccuum line.

When the engine is off the pedal is hard straight away, when i fire up the engine the pedal slowly sinks 1-1.5 inch or so as you've discribed.

 

Anyone got any more ideas??