I are in the middle of installing a 4 wheel ssbc disc brake conversion kit & were wondering if the proportion valve is required & where it is to be fitted or should the the master cylinder supplied have the correct pressures for 4 wheel discs. It is a standard brake kit.
thanks

An adjustable prop valve for the rear is usually all you need.

where do they normally mount . I have seen pics of them mounted between the master cylinder & distribution block but wouldn't that bring the brake warning light on with lower pressure to the rears . I have put mine where the residial pressure valve was on the chassis rail .
thanks

Correct. If mounted in the rear port line between master and switch, during hard braking it has the possibility of tripping the light. It should go in the rear brake line between distribution block and rear hose.
If you had the original brass block on the frame there before, that was the original disc/drum proportioning valve, not a residual valve. http://www.pozziracing.com/prop_valve_info.htm

Just a note,I did a four wheel manual brake with a change to front disk and didn't use the adjustable prop valve that came in the kit. I went from new master cylinder to old distribution block to new brake lines to new brakes...never had one problem with them

thanks for all your help guys , the instructions that came with the kit were pretty useless .if I only found this site a couple of years ago I would have saved some headaches.

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