Just a couple of pennies thought on that, if you don't mind: The intent of dual circuit systems is two-fold.
One, you get a safety redundancy if a wheel cylinder or caliper decides to puke fluid all over the place and empty the master cylinder. I've had several cars come in over the years that have been run so long on the front pads that the disc has ground away and allowed the caliper piston to pop out, dumping the fluid. Granted, I hope that no Inliner would do that, but Detroit operates under some different liability rules than we do.
Two, after installing a dual master, the package should also include fitting a proportioning valve. Kits sometimes have adjustable units since the supplier doesn't know your particular vehicle weight distribution. The valve allows the fluid pressure to operate the front and back brakes at an optimum level so the vehicle stops without using too much front or too much back brakes. To put it differently, since the load on the front and back brakes is not equal, the amount of braking should reflect that difference.
I posted this elsewhere on the B-board in a reply to a question on torsion bar suspension:
"I have a friend here at work who is updating a '65, and I gave him a dual-diaphragm booster and master cylinder that I had alreay customized from an S-10. He is keeping his original manual steering, so didn't have any interference problems like I had between that particular booster and the trans shift arm from the column. He wasn't interested in changing to disc, and is very happy with the all-drum power system (with no proportioning). He just ran one master outlet to the front and one to the back and split the pipes like I did."
I don't recommend a valve-less system. But you get the point about using modern master and booster systems on an otherwise stock lower end.
Give a holler if I can help out any more. BTW, I guess that was a little more than 2 pennies worth, huh
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David
