When installing front and rear disc brakes, the standard master cylinder will need to be replaced with a larger model that can move more fluid.
The standard diameter of the master cylinder is, depending on the year of manufacture, 17.46 mm or 19.05 mm for a single circuit braking system and 19.05 mm for a dual circuit system.
Larger master cylinders are 22.2 mm in diameter for the single-circuit braking system and 20.6 mm for the dual-circuit system. This allows you to move more fluid, which translates into equal force over a larger area, which is required for all 4 calipers.
Master cylinder for a single circuit braking system
It is equipped with a standard plastic reservoir or a reservoir made of aluminium. Both types are available in high quality A and, if the budget does not allow it, in low quality B.
For models with a plastic tank, the master cylinder and tank are of lower quality in B quality and of the same quality as the original in A quality. On the models with aluminium tank, only the master cylinder is of different quality, the tank is the same.
This master cylinder originally comes from a Volkswagen Split Bus, but it is often used for Baja's and Buggy's because of the fixed tank and if your Volkswagen Beetle or Karmann Ghia is equipped with discs at the front and at the rear. If you have a Volkswagen Beetle or Karmann Ghia with front and rear discs, this is the right master cylinder. This shows that this master cylinder can be fitted without any problem in an existing brake system, whether it is a disc or drum brake.
Extra note : If you choose parts of a lower quality it is only for one reason : the price tag. We can understand that, but don't forget that when you compromise on quality for brake parts you more or less also compromise on safety! That is a choice you have to make yourself, taking into account that you can never hold the seller liable and warranty is excluded.
Brake master cylinder for a dual brake system
This is provided if your VW Beetle or Karmann Ghia uses discs at the front and rear, but can also be but can also be easily fitted to an existing disc or drum brake system. The master cylinder has connections for two brake pressure switches. If your old master cylinder has only one brake pressure switch, you close the hole with a blind plug or with a second brake pressure switch which you do not connect. If you use two brake pressure switches, you can connect a warning light that will light up when there is a pressure difference between the two circuits, in this case use the 3-pole switches (see options tab).
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