no its not attached to the master cylinder its on the frame under and just back from the passenger seat. iv decided to just bypass it and connect the brakes lines with a few unions. seeing how its a front disk and rear drum brakes so its kinda pointless.
Its been my experience that the Japanese didn't do to many pointless things to automobiles in general. I would think that that valve might be handy when braking at speed going around a curve but I can't say that for sure. I think Low Range has them if you decide to replace it.
Doesn't have to be on a curve - unless the vehicle is facing the direction of travel 100% (which is extremely rare), the vehicle is likely to swap ends.
What the proportioning valve does is reduce the rear brake effort so that the rear brakes don't lock first, something that is qute possible on these vehicles where much of the weight is over the front wheels - in a panic stop, you get weight transfer forwards, further unloading the rear wheels, they lock, and you get to watch your rear end come around and overtake the front.
Not a good idea to eliminate the proportioning valve.
