Supra Forums banner
1 - 8 of 8 Posts

·
Registered
Joined
·
254 Posts
Discussion Starter · #1 ·
Hey guys I tried to look this up but couldn't get the answer I was looking for. On the MKIV TT it is stated in various threads that the master cylinder has a built in proportioning valve. Now I'm getting ready to start upgrading my brakes, tires, and wheels. I am trying to figure out how you guys are installing the proportioning valve. Let say for example i wanted to allow more pressure to my rear brakes. I am restricted to the pressure that the master cylinder is regulating to the rear brakes, correct? Do I need to block off the rear line output from the master cylinder and install the proportioning valve off the front brake output? If I do this would I be reducing the pressure from the master cylinder on the front output since it would be distributing to 4 brakes vs. 2 brakes?

Thanks,

Greg
 

·
Registered
Joined
·
254 Posts
Discussion Starter · #5 ·
Where is the stock proportioning valve located? All searches have pointed to the factory master cylinder having it built in.
 

·
Supra + DSM = heaven
Joined
·
3,946 Posts
well if your goal is to reduce rear braking, then you wont have a problem running a restrictor in addition to the factory piece. But you want to add more rear... If you are not considering to go an aftermarket master setup, you need to figure out exactly how the master is restricting it. If it can be modified or not (for example a screw i restrictor somewhere). I its the physical design of the master and cannot be modified, you can use brake pad selection or rear caliper change to move the bias back rearward and then give you the adjustment range you need by restricting the rear further with a prop valve. That will work, but optimal would really be a nice floor mount setup. Its lighter, easier to maintain and gives you more adjustability.
 

·
Registered
Joined
·
254 Posts
Discussion Starter · #7 ·
Right. Not that I'm afraid, but i'm not quite ready to crack open the master until I know for sure. I'd be curious to know what other MKIV owners have done with this. With upgraded front brakes and larger rear tires I can only assume that the front brakes will be over powering the rear.
 
1 - 8 of 8 Posts
Top