waiting for "my brakes squeal like a mother" comment
Zero squeal so far and I have not been gentle on the brakes. My old R Brakes did though.
Seems like you could leave the existing prop valve wide open (or eliminate it - reuse at the rear); and then merge the two rear lines into one - into a prop valve at the back - then split the output of this new rear prop valve to the two rear calipers. That should allow you to reduce pressure to just the rear brakes. Maybe that's what you meant by "replumb"....
I wanted a clean start and easily adjusted rear bias.
So I picked up some t's and plugs with the original intention was the Barton idea of using the factory block slider for the rears.
I eliminated the factory front slider and installed 2 10mm T's in their location, a little bending of the lines netted me an ok installation. I fabricated a small bracket to hold it all nicely together and keep the lines from rubbing on anything. All in all happy, you really cannot see anything from above. and its somewhat clean from below.
I eliminated the cross piping volvo B.S. The front output from the master controls the front 2 calipers, the rear output from the master controls the 2 rear calipers.
In effect this is now a normal brake system.
I then removed the factory proportioning valves and where I was going to put a bunch of plugs in the old block and install it, it just seemed way cleaner to install 2 10mmx1.0 unions. Amazingly I had 2 in my parts bin and tossed them in.
Backed out the rear prop valve and bled the brakes. They bled fast this time around and pedal feel was better than before and stiff.
It was still Dry before the monsoon came in so I gave it a quick spin around the neighborhood......WE HAVE BRAKES!!!! Like real brakes. Car stops hard and fast and now stops dead straight unlike before. I now have the ability to modulate just the rear brakes.
So moving on. I got the Racepak VNet oil pressure sender installed last week and was waiting on the new cable. It showed up Friday so I got that installed and chatted with them on the phone to get it working. A little programming and its good to go. I will say their tech support is far less than stellar. It was my 3rd call in to them and the first time we have resolved an issue. I still have no working VSS and speedo.
One of the other issues I stumbled onto was I omitted a vent from the fuel system when I hooked everything up and the car and trunk stunk like fuel.
I did a little digging around on the old interweb and found some useful info on the factory five forum. Guys were able to easily build a charcoal canister on their vent line and eliminate any smells.
Off to the pet store and home depot and we had this tidy little setup.
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This is all hooked into an anti rollover valve installed inside the factory fuel filler door. I was trying to get it higher than the filer neck and this was the only location I could make that happen. I hope that it works better and eliminates any smells.
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I also got the factory cover panels to fit over my new charcoal canister, got the other butcheek cover built from MDF and got the rear carpet fit.
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Not done in the trunk, It is going to get all trimmed out with a nice stereo in there but running out of time for Davis and LS Fest.
Hope to get some seatbelts ironed out in the next few days, door panels to upholstery shop and rear carpets all bound around the edge next week.
I leave for Davis in 18 days, 10 of them I will be out of town.
Sean