Larger master cylinder


Registered User
I have searched online for a larger master cylinder for the 8l s3/mk4 golf but there’s not much info about it, just a lot of dead end threads, there is some talk of a transporter one but nothing solid.

Here is my experiment, it’s a 26mm master cylinder and it involves turning the servo 90 degrees anti-clockwise and then fitting the re-drilled left hand drive master cylinder,

I have 18z front callipers already and I will be fitting the 4 pot rears


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Registered User
There is some work to do with brake lines and sensors that attach to the master cylinder, I bought a right and left hand drive version of the 26mm master cylinder so I could try both, I need to use the left hand drive version because the 2.5 tfsi turbo intake pipe gets in the way.


Registered User
Only thing to be wary of is ESP as there are sensors on the MC of ESP equipped cars...

This master cylinder only has a 4 pin combination sensor and the s3 uses a pair of 3 pin ones, I need to figure out if I can use the combination sensor or I may have to get creative to fit the second sensor.