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Front drum to disc conversion on a 69 Charger

RT Dreamin

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Hey all, I’m looking to convert the stock front drums to disc on my 69 Charger RT. I already have a kit in mind that will work with my stock spindles and I have confirmed it will work with my wheels. My question is, will I have to change the stock master cylinder and/or booster?
 
Master yes. Booster no.
I hate the red X so I have to explain why i disagree with this statement. The drum brake booster on a 69 Charger will not give enough boost to run those front discs. I went down that same road also before I found out that a single diaphragm booster will give you somewhere around 400 psi boost and front discs require about double the pressure. You need to upgrade the booster to a dual diaphragm unit or you will not be happy with the stopping power. There are a few threads on here dealing with that very issue. Do it right the first time and save your self some agony and money. You need to upgrade the booster, the master cylinder and the replace the distribution block with a proportioning valve to regulate the pressure to the rear brakes.
 
I hate the red X so I have to explain why i disagree with this statement. The drum brake booster on a 69 Charger will not give enough boost to run those front discs. I went down that same road also before I found out that a single diaphragm booster will give you somewhere around 400 psi boost and front discs require about double the pressure. You need to upgrade the booster to a dual diaphragm unit or you will not be happy with the stopping power. There are a few threads on here dealing with that very issue. Do it right the first time and save your self some agony and money. You need to upgrade the booster, the master cylinder and the replace the distribution block with a proportioning valve to regulate the pressure to the rear brakes.
Thanks for the info, I think I saw some kits that were the booster, master cylinder and the valves. I’ll take a closer look at that one.
 
I hate the red X so I have to explain why i disagree with this statement. The drum brake booster on a 69 Charger will not give enough boost to run those front discs. I went down that same road also before I found out that a single diaphragm booster will give you somewhere around 400 psi boost and front discs require about double the pressure. You need to upgrade the booster to a dual diaphragm unit or you will not be happy with the stopping power. There are a few threads on here dealing with that very issue. Do it right the first time and save your self some agony and money. You need to upgrade the booster, the master cylinder and the replace the distribution block with a proportioning valve to regulate the pressure to the rear brakes.
I second that you will need the dual- diaphragm booster.
 
Master yes. Booster no.

I just used my stock valve on my 69 Charger.
I usually agree with Pnora but I think you’re wrong on this one.
Front disc brake systems need more boost and a proper proportioning valve.
When in doubt, do what you can to duplicate the factory system.
 
Thanks for the info, I think I saw some kits that were the booster, master cylinder and the valves. I’ll take a closer look at that one.
I got mine from Pirate Jack. The booster has a larger rubber boot that goes through the firewall so you will have to enlarge the hole just a tad with a dremel or a file. Other than that, it will bolt right in.
 
My 69 was 4 wheel drum manual brake. I went with the advice from Dr. Differential [Cass]. I run the Wilwood front disc's, Ford SVO Motorsport rear disc. Manual brakes with the stock valve. This car stops perfect. Cass said I might need to run an adjustable pressure valve to tune the rear if needed. I did not need it. This car plain *** stops. I am sure any booster would decrease the effort but at this time I would not change a thing. I can only relate to what works for me hence any replies I made on this post references my results.
You have rear discs. Big difference. You would not need the proportioning valve. Only with rear drums.
 
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