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Discussion Starter · #1 ·
Right here goes, I'll start with the system I'm running.
Wilwood limited space single circuit master cylinder 1 inch bore.
Remote Girling servo, Wilwood Superlite 4pot calipers on the front 35mm pistons.
on the rear I've got Ford Sierra single piston rear Calipers 42.8mm .
I'm pretty sure all the air is out of the system but I can't seem to get a proper hard pedal. No matter how hard I press I can't get the wheels to lock up. I apply the brakes and the car stops but in its own time. I did bench bleed the master cylinder before fitting. I had princess 4 pots and it was doing the same thing. Could it be the servo?
Any answers much appreciated.
 

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Gym Junkie
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Make sure the bleed nipples on the callipers are pointing straight up, if they are at an angle you won't be able to get all the air out, is the master cylinder lower than the callipers, if it is then residual valves may be needed to stop the fluid draining back and keep some pressure in the line, 2lb for discs, 10lb for drums.
 

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To me, 1" bore is a little over the top on that combination and losing too much line pressure for best efficiency. As others have said we need to start at pedal ratio first and take a few measurements based on that to see what's happening.

So , first pedal ratio and then measure amount of travel of pedal from resting to floor and then fully applied pedal to floor please.
 

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Make sure the bleed nipples on the callipers are pointing straight up, .
this is where your prob lies I reckon. Wilwood normally have bleeds top and bottom to save them making left and right handed versions. You can often get air stuck down in the bottom bleed. Unbolt the caliper and rotate it so the bleed is at the top, bleed and refit.
 

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Discussion Starter · #8 ·
this is where your prob lies I reckon. Wilwood normally have bleeds top and bottom to save them making left and right handed versions. You can often get air stuck down in the bottom bleed. Unbolt the caliper and rotate it so the bleed is at the top, bleed and refit.
I don't think this is the problem as the problem was there when i had the princess calipers on it. The Wilwood nipples point straight up.
I will check the pedal ratio tomorrow and see if that is the problem.
Thanks for all the answers.
 
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