63 convertible_ drum brakes, adding booster and dual mc

[Steve D.]

In a previous thread re: braking effort, adding a booster was suggested. I talked to Luke at CSSB, Inc regarding their package for adding a booster and dual mc for a 63 with drum brakes. The booster is the 64-67 booster, and the mc kit is for 63. I brought up the hood clearance issue and was told that making adjustments as needed to the booster bracket during installation will take care of that. The mc kit comes with replacement lines, check valves, blocks etc. I'm still unclear why the lines have to be replaced. I realize that a separate circuit is being added, but I assumed that plumbing to separate blocks would be sufficient. Are the new lines slightly smaller in diameter due to the booster? (I neglected to ask). I checked the archives and read several threads. My car is a driver and correctness for judging is not a particular concern. Any words of wisdom for the install would be appreciated.

Steve

[Duke W.]

Re: 63 convertible_ drum brakes, adding booster and dual mc

A vacuum booster makes sense, but why switch to a dual master with all the associated plumbing modifications.

The hydraulic system is simple and fundamentally very reliable. Problems arise due to lack of maintenance for decades. The big problem is water absorption by conventional glycol-based brake fluid, which eventually causes corrosion resulting in failure of a component to hold pressure. This can be circumvented by periodic - every few years - flushing of the old fluid for new, but few cars receive this critical maintenance.

If you rebuild all the hydraulic components now, which is not a difficult task, flush out all the pipes with denatured alcohol, and assemble everything with DOT 5 silicone fluid, then fill and bleed the system with DOT 5, the system will probably be okay for 20-30 years without flushing since DOT 5 doesn't absorb moisture, but flushing ever 5-10 years will probably give well over 30 years service life for a collector car that is stored inside and is not usually driven in wet weather.

Duke

[Scott P.]

Re: 63 convertible_ drum brakes, adding booster and dual mc

Steve, the reason you have to change lines is that with the Dual MC the rear line is moved from the brake block in front of the steering box and installed into the rear port of the MC and the line will be too short when the booster is added. Usually the line that currently goes from that block to the stock MC will be long enough to reach the front port of the Dual MC. An inverted flare plug will need to be installed in the brake block when the rear line is removed and plumbed to the Dual MC.
There is no need for any check valves or different block if you use a plug.
Lone Star Caliper has a several kits to do what you want and if you get their repo 67 Dual MC stamped DC the conversion will look good.
Another reason to change lines, 63 lines were 3/16 and the Dual MC will accept a 1/4 line with the correct fitting but not smaller. You can use an adapter but it dosent look as good.
There is more if you are interested. Thanks Scott