I've been reading all up and down and can't seem to find a definitive answer. I found a pretty detailed page about upgrading to a dual master cylinder in a 64 Wildcat using a 67 Wildcat master cylinder but not sure If that's the same info needed for a lesabre. I ordered the scarebird front disc brake swap kit, and it doesn't really have much info for which master to use, only shows a adjustable proportioning valve in, but I'm wanting to upgrade to a dual master cylinder setup for a little bit better setup. Any info would be a huge help! Thanks!
That is always the problem! And Scarebird will tell you that you can use the original single MC with no changes. (BS)
So do you know if the 67 wildcat master cylinder works? It crosses with a bunch of other gm master cylinder and stocked at my local parts store so it would be nice if that's the one I need
NO -- it will not -- the 1967 Buick Wildcat Master Cylinder your local parts tore looked up -- IS a 4 wheel drum brake master cylinder --- that WILL NOT work with Front Disc Brake / Rear Drum Brake Scenarios..............
Actuslly I looked it up myself because I don't trust parts store people lol. It's the front disc rear drum option, just wasn't sure if the depth and size and bolt pattern were the same, or how to check without disassembling my car first
The rod depth is the thing that you have to watch out for. Look at your master or take it with you. Do not trust them. Don't ask how I know.
The LeSabre and Wildcat booster and master cylinder are the same. You may have found my page about converting to a dual master cylinder at http://www.1964buick.com/resto_logs/dual_master/1964_Wildcat_dual_master_cylinder.htm. If I was a betting man, I would assume since a 1967 Bendix (instead of Delco) fit on my 64 booster, if you bought the dual master cylinder for the disc setup for the 67 Bendix it would work. Recommend you buy one locally, cover the pushrod with a plastic bag, and trial fit.
Yep I gave read your build several times. And my problem I'm facing now is I did the disk brake swap. And every master cylinder I can find is for drum drum.. I cannot seem to find a master cylinder for the bendix with disk/ drum. And I also am. Having a hard time finding a new booster I could switch to that I can use a shallow master cylinder with. If you have any info on this, that would be amazing!!
When I swapped my '64 Riv. to discs from a '70 Estate wagon back in the early 80's I used the '70 M/Cyl. I had to take apart the original booster to modify the push-rod length. Measured 10 times. Took little cuts at a time till the length was correct. Then I was able to "Fine" tune it with the adjustment on the original push-rod.
Yea Ive had to modify a booster like that before, but in this case the amount I would need to cut off would be into the hard plastic molded into the diaphragm. There would be no metal rod left, so I don't think that's really a option
After perusing Rock Auto, I see the problem you are in. The only disc master cylinder sold in 1967 needs a different booster, and I have found those boosters hit your shift linkage if you have a column shift car. Doing some googling, it seems the two differences between drum brake and disc master cylinders are residual valves on drum m/cs and the fluid tank for the disc circuit is bigger. If you could find a way to remove a residual valve, you could use a drum m/c, but me personally I wouldn't want to do that. If I was in your situation, I think I would buy one of the many universal 7", 9", etc booster/master cylinder kits. Going that route you take all the booster to m/c fitment out of the equation, it will come with a proportioning valve and all brackets, and the single variable you have to deal with is the booster to brake pedal interface.
I think i may have found a solution! A 67 firebird had the option of a deep piston hole with disc front drum rear. I have got the master cylinder and it fits, I will hopefully be testing today to make sure everything works and stops right! I'll keep everyone posted
