I'm interested in tying the Subaru 1980 dual brake masted cylinder. I would like to know how to re-pipe the brake lines especially regarding the five-way connection on the passenger fender well. Does the front reservoir go to the connection block and the rear reservoir directly to the rear brakes and add a plug to the five-way connection block where the rear line previously attached? I would appreciate input from anyone that has converted to a dual reservoir system.
Does anyone have recommendations on re-piping brake lines with a dual brake master cylinder??
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The rear connection on the tandem master cylinder feeds the front brakes thru the original feed line to the switch block. . The simple method would be to pull the rear brake line from the brake switch block and plug the exposed hole with a 3/8" X 24 bolt. The rear brake line gets re-plumbed to the front connection on the tandem master. Different owners plot different routing . As long as the fluid gets where it is supposed to.
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If you're going to do all new lines, I would eliminate the switch block. It's really only needed for a single circuit system. I ran the front line out through the inner fender and to a T-connector on the cross member. Out of this, one line to the left caliper and one across the cross member for the other side. You can still use the existing clips to keep the line in place.
For the rears, I ran a line across the firewall to a proportioning valve where the booster was and from there it follows the stock routing. You'll need to add a fitting for a brake light switch or go with a mechanical switch by the pedal.
As mentioned there are other ways but I was very happy with how neat and clean it came out.
For the rears, I ran a line across the firewall to a proportioning valve where the booster was and from there it follows the stock routing. You'll need to add a fitting for a brake light switch or go with a mechanical switch by the pedal.
As mentioned there are other ways but I was very happy with how neat and clean it came out.
Austin Healer
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You are probably going to want to find a distribution block for a dual circuit system with a proportioning valve. Otherwise you'd need to put a proportioning/bias valve in line with the rear brakes so you could adjust brake bias properly.
Just an FYI. In late 1967 Sunbeam started using a Lockheed brake system with a dual brake master. The rear cylinder of the master was connected to a Lockheed booster and was connected to the front brakes only. No boost to the rear brakes. The front cylinder of the master was connected to the rear brakes. They did not use a proportioning valve. Would a system set up this way work on a Tiger using rear drum brakes with disc up front?
Thanks for the recommendations. I'll post what I do once I get the car back from the bodyshop and start putting it back together. I appreciate the input.
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Make sure you have the proper fittings on each of the brake components. You may end up with different fitting threads (metric, British, SAE) at the master, proportioning valve, and OEM parts, and different flare types may be required on the lines. It’s not a big deal to cut and flare your own lines as long as you have the right tools and some patience.
If you can put in a mechanical brake light switch that acts on the pedal arm, then it eliminates another potential hydraulic leak point in the brake system. It also can be set so that the brake lights come on as soon as you depress the brake pedal even slightly, which gives increased warning to the following drivers compared to the pressure switch operation.
If you can put in a mechanical brake light switch that acts on the pedal arm, then it eliminates another potential hydraulic leak point in the brake system. It also can be set so that the brake lights come on as soon as you depress the brake pedal even slightly, which gives increased warning to the following drivers compared to the pressure switch operation.
Thanks for the advice. I'm retired now but owned an electrical and HVAC company. I have the tools and ability to make the ends. I bought the Classic Tubes SS preformed lines for the expediency of installing the lines. I just recently decided to do the dual master cylinder.