A Poor Man's Master Cylinder Upgrade

Gerald Morris

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Great article. I am currently doing this very upgrade. I noticed a question regarding master cylinders for manual disc brakes. My 1973 Charger had manual disc/drums that worked like a charm, required minimal foot pressure and never caused me any concern during some 36,000 miles of hard driving (I was young). This is a fairly heavy car, too. A quick check of the parts books for that master might prove helpful. Can't wait to complete this upgrade!

Check it out. It may well be the same size as the '67 Bendix, but would be proportioned more heavily toward the front, where the discs are. The Dodge FSM for 1973 probably mentions the model and make of that master cylinder.

I suspect that if you went with anything like the old Budd dual piston calipers, those would HAVE to use a boosted cylinder, but I admit to having seen some stuff for manual disk brakes since I did my job that compels me to admit they may be done so. Mind you, I'm very pleased with the all drum system I currently have. If I ever were to install after-market disc brakes in any conversion, I likely would use Wilwood products.....

I pray your job works out well for you.

Happy Moparing!
 

JimmyG

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I am pleased to say Mr. Morris, that I am staying with drums on all for corners, and am swapping to the 12" system. I am working on a '61 Newport one very slow piece at a time, using the same master as in your article.
 

Gerald Morris

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I am pleased to say Mr. Morris, that I am staying with drums on all for corners, and am swapping to the 12" system. I am working on a '61 Newport one very slow piece at a time, using the same master as in your article.

MOST WISE! Did you get an original Bendix or the copy that I bought? Must say, after a year, its performed flawlessly. 12" drums should be PLENTY of stopping area to arrest motion. I'd just about sell a testicle for a Forward Look station wagon. LUV those old high compression motors too.
 

Gerald Morris

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I suspect a copy. Bought it from NAPA,...no testicles involved.

I'm sure it's a copy. The slave foundries of the East seem to have got their molds right for casting good copies of the venerable Bendix MC. Been totally Happy Crappy with mine, without so much as a malcontent wriggling gamete either! You have a good piston rod for the pedal, with the little retainer rubber and stuff?

I still trust NAPA as far as I can punt their staffers, unlike some of the more blatantly convenience store model auto parts shops.
 

JimmyG

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PART NUMBER UPDATE: Given that Weatherhead fittings can be difficult to find, I have converted to Edelmann fittings, and secured them no problem. Here is the conversion:
Weatherhead 7909 = Edelmann 258350
7910 = 258303
131X4 = 120400
302X3 = 123300
Hope this helps.
 

Gerald Morris

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PART NUMBER UPDATE: Given that Weatherhead fittings can be difficult to find, I have converted to Edelmann fittings, and secured them no problem. Here is the conversion:
Weatherhead 7909 = Edelmann 258350
7910 = 258303
131X4 = 120400
302X3 = 123300
Hope this helps.

Good contribution for future upgrades!
 

TxDon

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Gerald, thanks for leading me to this thread, your description and parts list is excellent and answers most of my questions about fittings.
 

Gerald Morris

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Gerald, thanks for leading me to this thread, your description and parts list is excellent and answers most of my questions about fittings.

Quite welcome man! I composed this with folk like you in mind. Plenty C body fanciers like the 65-66 form particularly, which IS an EXCELLENT one in my book, but it still has a few legacy issues like the single brake circuit, which can be a FATAL fault.. So, an easy, affordable upgrade path serves the Community well.
 
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