If your fronts are locked you can not steer your buggy. So far I have never seen a panic situation that I would want all 4 locked. But I usually stay on the trails that go to Wal-Mart.

The proportioning valve I use is the cheap $20 one which allows you to turn off all the pressure to the front brakes.

Might as well add my 2 cents. I had seperate brakes on my last Buggy an liked it a lot for all the reasons KY and others stated. When I built my Turbo Buggy I went with all four on the pedal and found I did not like it much for the same reasons KY and others stated. So over the winter I went to a seperate front brake on its own master and handle. I know i will like that a lot better. I also went to Saco Billet 4 puck calipers and 11" rotors in the rear. I felt with the new Peliqin differential I am gonna need much better turning brakes.

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Water cooled Dry Sumped Subaru Powered Turbo Charged Fuel Injected 2500CC Tank. Oh Rah! He who dies with the most Toys not only wins, He also wears them out!