twintracks

Hi All,
I'm currently restoring and preparing a 1937 Oldsmobile L-37 Touring Sedan for entry in the 2014 Great Race from Maine to Florida in June. I have been advised that a wise modification would be a dual master cylinder for added safety. Safety mods can be done with no penalty. Has anyone ever converted an older stock drum brake car to a dual master cylinder? I'm looking for expert guidance on the correct cylinder bore size? Also, what can be done in-line to make the front & rear pressure independently adjustable? The race is never over 60 mph, so disc brakes are not needed, plus I'm just not that hard on brakes to begin with. This is simply a safety thing. We are also converting the stock 4.23 rear end diff, for the 3.23 diff from a '49 Olds for better highway speeds.

Thanks, Jerry

mpolds

This would not be a quick and easy conversion -- because with a frame rail master cylinder that the 1937 Olds has, you can'e have "gravity feed" which is why Master Cylinders were brought up to the firewall....

There are some disc brake conversion companies that do have non-gravity-feed booster / dual master combos -- but they are expensive, not an easy conversion, and many people that have tried them have issues with them..

Sometimes, the phrase "if it ain't broke, don't fix it" applies......

Incidentally -- I do have the Master Cylinder BRAND NEW -- new fresh stock housing, new fresh stock guts, etc. etc. with NO CORE -- if you want one or want an Extra One..... And, I do have exactly three (3) FRONT HUBS & DRUMS -- N.O.S. !!!!!!!!!!!!! -- for 1937 - 1938 OLDS +++ ONLY +++ (Talk about non-existant on planet earth!!!!!!!!!)

Call me -- Craig -- 516 - 485 - 1935 .... New York..

joe_padavano

Yet...

There are hundreds of thousands of street rods with dual master cylinders mounted on the frame. You certainly won't find anything bolt-on, but there are a multitude of mounting brackets available (admittedly, most for Fords), which are designed to accept standard GM dual circuit M/Cs. Here's one of many universal mounting kits available. You can use it with manual or power brakes. Residual pressure valves are used if the M/C is below the wheel cylinders. Some M/Cs have these built in, so verify what M/C you have before adding valves.

Note that vehicles like the late 1960s Jeep CJs used dual circuit M/Cs mounted to the frame from the factory, so there's no "magic" to making this configuration work. M/Cs were moved to the firewall mainly to make them more convenient to work on, especially when brake pedals changed from bottom pivot to top pivot. It's kinda hard to mount the M/C on the frame if the brake pedal is pivoted from the top.