I DON'T have equal line pressure because of the adjustable prop valve, and as I said the disk on disk prop valve is NOT a 50/50 pressure valve anyway. I do know my system works excellent, I change front pads 2 to 1 over the rear. You may be an expert but I know what works!!
You need to go back and read what you are telling folks to do. First you imply that going to a disc/disc combo valve is the way to go and then you go on to tell them that you need to reduce the pressure further out of that with an adjustable prop valve in order to keep the rears from locking up.
Had you just left it alone, provided it is a TJ combo valve, you would enjoy exactly the same results you have now with less money spent, no new lines being made, and less complexity in the system.
BTW, I'm not familiar with your particular disc/disc combo valve, but most of them are split 50/50 front to rear because there is no need for a knee point in the pressure output to stop the servo nature of the rear drums.
Drum brakes past a certain pressure point are self applying which is also why they have very high force return springs. Due to the self applying nature, the pressure is cut off at a certain point and stays there to stop them from locking up.
Bias in a disc/disc system is done by the size of the components. The rear caliper is typically 50% smaller and the rotor is much thinner, non vented and the pads are very small when compared to the front.
I'm also not sure what you meant by 65/35. All aftermarket adjustable prob valves are only capable of reducing the pressure by 60% which means I can't tell from the way you wrote it if you are using it at 35% or 65% and I'm assuming it must be a 35% reduction because it won't go 65%.
