Wilwood 4 pots problem


Balls! I was hoping you guys had done the rears and it was the increase in the size of the pistons there pushing you over the edge. no such luck.
 
well mate drove mine today its drivable and even though the pedal is a bit spongy still the pedal after a few pumps is hard so i think another bleed is needed will do it next weekend. but the problem is really not locking the fronts up if you only touch the brakes the ABS kicks in looks like i need better tyres the T1R's cannot handle such brake power.

anyway will update this as i go allong for now it's drivable.
 
After 250miles the pedal feel little better but still a lot spongy, i will try in the next two days re-bleed all system and hope it works. If not work and i dont see any problem on brake line maybe its time to 1" MC :(
 
I'm planning on fitting my wilwoods by friday - using a 1" MC and matching servo. I'll let you know how mine turns out.
 
clockwoRk said:
I'm planning on fitting my wilwoods by friday - using a 1" MC and matching servo. I'll let you know how mine turns out.
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She will turn out beautifully !

I have the Wilwood 4 pots up front, 260mm rear ITR brake conversion on the rear, braided lines etc. Motul RBF600 a 1" ITR master cylinder and servo and have had zero problems from day 1 which is over a year ago now.
 
Im looking for lhd ITR 1" MC but nothing until know :angry:...for lhd ek its better lhd itr as connections on master cylinder its the same with no bending lines :nice:
 
Mallyauto86 said:
there's a few knocking arounde mate...
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for my left hand drive ek4 i need one like this

2012-04-19%2016.26.44.jpg


The mc for right hand drive the left nipple its on right side

If you know any MC 1" dc2 left hand drive let me know
 
i see. will see if i can find one ... not sorted my problem out yet anyway will update as soon as i get it sorted though
 
Try bleeding all system this morning with no lucky...bleed bleed for about 30minutes and pedal feel the same,no air buble come from calipers :(
 
my pedal feels strange too but it's drivable... i dont think this will cure the problem either i think to solve the problem it's going to need a 1" ITR MC with a bias valve ...
 
Its drivable with no problem at all. if i brake hard the brakes have enough power to activate abs in normal road but pedal have to much travel...

Maybe only 1" mc will cure this...
 
Mallyauto86 said:
my pedal feels strange too but it's drivable... i dont think this will cure the problem either i think to solve the problem it's going to need a 1" ITR MC with a bias valve ...
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I don't think a bias adjuster will help with pedal feel. to my understanding it just allows you turn the pressure down on either the fronts or rears - most people fit them for the rear brakes so the fronts are always full and you turn down the rears to give more bias to the front.
 
Just to check that this is within what you guys are experiencing:

15/16 MC has a .69in2 cross sectional area.
VTi caliper has a 3.56in2 cross sectional area.

To move the caliper piston 1/4", you need .25 x 3.56 = .89in3 of fluid.

For the MC to move .89in3 the MC piston needs to move .89/.69 = 1.29".

Through a pedal ratio of 5 that's 6.45" travel on the pedal for .25" at the caliper.

Same workings for Wilwoods with 4.81in2 piston gives you 8.71" pedal travel for the same .25" at the caliper, an increase of 2.26" over stock.

If that is the sort of increase in travel you feel like you are getting, then your MC is too small. A 1" MC will bring it back to 7.65" pedal travel, an increase of 1.20" over stock.

Big pistons are bad mkay, they really do screw up more than they improve. I would recommend anyone fitting this setup to an EK4 to opt for the smaller 38mm pistons if you want the setup to work well with your existing brake system. The smaller pistons have an area of 3.53in", virtually identical to the stock caliper. No pedal travel issues, no screwing up the bias, just the benefits of lighter calipers and better pedal feel.
 
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I think kozi are right,for work ok in ek4 must buy 38mm piston caliper. for ek9 maybe 38mm have small area than stock dont know

twins spoon have 2x 38mm and 2x 43mm
 
Id like to know piston area for setups like tama666 and stevenek9 that use huge brembo calipers and works fine with 1"
 
EK9 caliper has 3.94in2 area. The 38mm Wilwoods will be too small at 3.53in2 (-10%), the 45mms too big at 4.81in2 (+22%).

Going for the bigger pistons won't be as much of an issue as it is on the EK4, but I would still go for the smaller pistons out of the two personally as it closest to stock and being slightly smaller it gives you more rear bias.

Tama's calipers are 3.72in2.
Stevens are 3.53in2.

Good brakes, small pistons. ;)
 
Thanks kozy :)

if i will buy know wilwoods maybe ask for 38mm even with 1" mc....something in the middle like spoon give oem piston area.

but know i have this 44mm i will buy 1" mc to install i will not sell this to buy another set of smaller pisont calipera
 
the idea of the brake bias valvle is to take off some of the power up front and ofcorse i wil still be upgrading to a 1 inch MC i'm sure that it would be perfectly fine with this combination.
 
Mallyauto86 said:
the idea of the brake bias valvle is to take off some of the power up front
Click to expand...

It's doesn't work like that, all it will do is reduce pressure to the rear, it will not change anything about the front brakes.
 
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