As the rear axle evolution progresses, I am becoming more and more happy with the results. After a few nights of diligent work, I am to the point where I will start prepping the axle housing for final color very soon, and that will make way for the final modifications to the 4-link suspension. However, before I get too far in that description, there are a few interesting things I need to document here first.
“Cunifer” Hard Lines
Pronounced “Cue•knee•fur” – the word cunifer is actually an acronym referring to the metallic composition of the brake line tubing most people have never heard of. Specifically, cunifer tubing is an alloy of copper (Cu), nickel (Ni) and iron (Fe) and has been around for over 70 years. The material is extremely corrosion resistant, bends and flares very easily, and is very durable. And while the material is a copper-based alloy it is NOT conventional copper plumbing tubing in any way, shape or form.
In hot rod circles, stainless tubing gets big play because it’s shiny, durable, and obviously corrosion resistant. The good news is that many pre-bent brake line kits are available in stainless for restoration ease as well. But what if you are doing something from scratch or want to clean-up the appearance of the installation over what the factory installed? In most cases, you are on your own, and generally speaking, stainless steel brake tubing is harder to work with and expensive, especially for the do-it-yourself restoration enthusiast. In fact, other than “off-the-roll” appearance, there really isn’t any advantage to stainless steel brake line material compared to cunifer.
When was the last time you saw stainless steel brake lines on a production car? Even an exotic, high-end sports car for that matter? Fact is, in 99% of brake applications, they don’t use stainless brake tubing. In fact, more high-market car manufacturers use cunifer tubing than any other. Rolls-Royce, Porsche, Audi, Aston Martin, and Volvo all use cunifer brake line tubing exclusively. Japanese and US car manufacturers are the remaining hold-outs that continue to use conventional coated steel (not stainless) tubing due to the pervasive “low-bidder” mentality that dominates these markets.
|Cunifer brake tubing is wonderfully easy to form with simple tools. Note the protective stainless steel spring around the tubing to prevent damage from road debris.|
|Here is the rear brake distribution block with the newly formed cunifer hard line in place.|
|The hard line is routed around the periphery of the 3rd member for a clean look.|
|Here is a look at the passenger side of the hard line. Bends are smooth with no hint of kinks.|
Rear Disc Brake Trial Fit
As the modifications to the axle housing approach completion, the time had finally come to trial fit all of the Street or Track, LLC rear disc brake conversion parts I had collected for the car to ensure everything fit as intended and clearance issues could be addressed before applying final finishes to the rest of the parts. This would also mark the first time I could test fit the axles and complete set of brake lines to the housing as well.
I am happy to say that the brake kits installed quite nicely and the installation instructions were quite easy to follow. I played with caliper position a bit but quickly discovered there was only one position that would allow adequate clearance to all components, so that’s what I stayed with.
Once I was satisfied with the caliper installation, I fit all of the rear brake lines (hard and soft) to ensure proper fit. Here again, the Street or Track parts worked superbly and I could now move forward with final prep of the housing before sand blasting and coating.
|This is the Street or Track rear disk brake kit mocked up on the left rear of the axle housing. This is the "busiest" corner of the car and I discovered the fit to be perfect for my 4-link suspension.|
|here is the left rear brake kit installed (without brake pads).|
|The right rear brake kit is equally nice an installation and a considerably less crowded corner than the left.|
|Left rear disc brake conversion mock up is complete!|
Coilover Lower Mount Bushings
|Using a commercially available bushing, I was able to weld it into the original 5/8" mounting holes. This was necessary to mount the new Bilstein coilover dampers as they use 1/2" fasteners instead.|