brake set up ?

[Foley]

Basically i've had an issue with my brakes for a while now and seeing as i'm turning the car into a track toy i want to sort out the whole system ! What i need to know is how do i go about removing the brake servo and running with out it ie rally/race cars ? I will be running standard calipers on rear (uprated discs and pads ) and wilwood 4 pots on front ! Thank you in advance for your help :D

[16v_paddy]

What issues are you having with it?

I'm running a similar set up, wilwood 4 pots with ebc discs & pads and std at the rear

[Foley]

basically after 15 mins of driving the pedal goes hard and the only way to get the pedal back is take off the breather hose off the back of the servo or place my foot under the pedal and lift it up ! I have checked the one way valve and that seems ok ! So i'm stumped on it and decided to do away with the servo but i just don't know how to ! :cry:

[MAXIBOY]

sounds like the one way valve or a problem but i wouldn't run without a servo

[16v_paddy]

:shock:
Okaaay, never come across that problem b4 :?

[white16valver]

You'll have to have legs like schwarzenegger to run without a servo! lol

[Foley]

you say don't run without a servo but what do the rally boys use ?

[MAXIBOY]

they use a bias pedal box with twin master cylinders set up for whatever they need...

overkill and not available for the clio off the shelf as even the maxi's ran a servo system as did all the work's rally cars

might be worth upgrading the master cylinder but i haven't as yet felt the need...

[Foley]

upgrade the master cylinder up to what as i wouldn't have an idea ! :oops:

[MAXIBOY]

think there's a laguna one with a slightly bigger bore thats a direct fit..

[richy]

id just leave the servo as is, just fit a new one if its not the one way valve etc at fault

depending what 4 pot piston size you go for you can increase the clamping force on the pads/discs but this will increase the pedal travel, or the opposite reduce clamping force but reduce pedal travel.

obviously you also want to make sure the rest of the system is good too!

[Twincam]

If you want to run without a servo just block the vacum line and take the one way valve out, but if i was you i wouldnt bother servo assistance is far better

youl also find that most rally cars that have pedal boxes are cars that never had servos in the first place or run anti-lag which means disconnecting the servo anyway

[white16valver]

Why do you have to disconnect the brake servo if you're running anti-lag???

[Twincam]

due to positive pressure in the inlet instead of vacum

[Foley]

think there's a laguna one with a slightly bigger bore thats a direct fit..



Does anybody have any idea which laguna one fits ?

[MAXIBOY]

i'll check think i have numbers some where...but its really not needed for four pots..will increase pedal travel for a small increase in pressure..

[white16valver]

due to positive pressure in the inlet instead of vacum
I'm confused :oops: lol

[stevie_b]

With ALS the turbo compressor is still running when the throttle is snapped closed, so you end up with positive pressure in the inlet (which then bypasses, allowing the turbo to continue spinning and reduces turbo lag)

[white16valver]

So how is the brake servo related/connected to the inlet manifold???

Sorry for dumb questions lol

[MAXIBOY]

on a n/a car the servo uses the vacuum from the inlet to aid you pressing the brake pedal by way of a large diaphragm

[white16valver]

I have no idea how that could work :oops: but thank you for the explanation :) lol

[stevie_b]

I have no idea how that could work :oops:

This article might be of interest to help:

http://auto.howstuffworks.com/power-brake1.htm

[white16valver]

Cool link, cheers :)

I think I get it now... lol