’32 Update: Brake Lines (article 26, archived)

Brake Lines
If you were wondering how I ran my brake lines, this will be the article which answers that burning desire.

Starting at the front, I brought the braided line out of the Wilwood caliper with a 1/8 NPT to -3 90 degree fitting. Because this is an open wheel car, I decided not to run the lines directly to the frame rails because I wanted them to blend in as much as possible. Short of wireless brake line technology that hasn’t been approved by the NSRA yet, I felt this was the next best thing. Using a 9″ braided line (as opposed to a regular brake line kit which is around 16″) I dropped down to the tie rod. I could use such a short line because the only movement is in the very slight angle change of the tie rod and steering arm. In suspension travel, the flex line has to put up with a similar angle change, this time in a vertical arc. Again, it’s peanuts compared to the angle change between the caliper and frame rail during a turn.

I machined clamps to hold the -3 joiner on to the bar and also machined the hex off the joiner fitting then centered it in the clamp. A set screw on the bottom of the clamp holds them to the bar.

Let’s play “where’s the brake line?”

I ran both sides to a T fitting under the drivers side frame rail, slightly offset to the engine side so it’s harder to see as you walk up to the car. This is where the most flex will occur, because the tie rod is going back and forth under the rail.

The middle flex line goes back just behind the steering box where it meets up to the hard line. Instead of using a bulkhead type fitting to connect the lines, I drilled out a front panhard bar tab (from Welder Series of course!) to just under 7/16″. With a bit of filing on the tab, the round part on a 3/16″ fitting will press in to it, and hold securely. It can’t come out because the hex is bigger than the round part of the fitting. If you have one in your hand, you’ll see what I mean. A -3 joiner holds the other side of the tab.

Further back, we see the Wilwood 10# residual check valve in place, attached to the line with two -3 to 1/8NPT fittings. I used another panhard tab to hold the frame end of the braided line. Braided line is being used just in case we want to use a power booster some day. All we have to do is add the booster… no bending up new lines. It also makes it really easy to drop the master cylinder if we need to look inside it for some reason.

From the braided line going to the rear line, I attached the proportioning valve right to the residual check valve with a 1/8NPT to 1/8NPT joiner. The frame rail got tapped to hold the prop. valve. Yet another panhard tab holds the braided flex line coming from the rear drum. The other line goes along the rear crossmember to a flex line on the passenger side.

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