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post #2 of (permalink) Old 07-12-2019, 12:38 AM
Join Date: Jul 2019
Location: Pierce County, Washington
Posts: 51
Originally Posted by malstrom View Post
Hi Friends

So I think I have the theory in my head correct. If I buy the enclosed link master cylinder. I would not be able to hook it up with a 4 drum brake vehicle without adding a 2 inch long inline residual valve and perhaps the valve in the master.

Which means if I want to convert to a front disc upgrade kit at some future point I need to modify brake lines again.

Ideas ?

Thanks !

Residual pressure valves are recommended, but the number of drum to disk conversions that omit them, without even realizing, is somewhat staggering. You would want a residual pressure valve and you'd probably want one inline to both front and rear circuits if using a non-drum master (this one appears to be disk / drum - so make sure there is no residual valve in the rear circuit already from the master cylinder). All drum / drum systems I'm aware of used residual valves @ 10PSI +/- to both circuits, but I'm not a "Mustang expert" so, take that for what its worth. You would NOT want to retain the combination valve however (looks like a standard Pv2 unit) - It would direct and delay pressures inappropriately for a drum / drum system - that being the case, you'll need to re-plumb your brake lines anyway if you move to disks later.

A note on residual pressure valves - those suckers leak. I mean, perhaps not all of them, but I've found them to be yet another weak link. You might look into an appropriate thread sealant - its the only way I've got them to hold, you shouldn't have to technically, but such as it is.

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