That was exactly what I did on my 66 Polara. I can't think of why it wouldn't work on a 300.
DuaneBallard wrote ...
jazzandmoparguy wrote ...
I would even say it's easier... just buy a 67 or 68 dual res DRUM master cylinder for your car, and bolt it on, and use this kit: Thanks Mike! I'll order one then.
If you are planning to do a disc upgrade, then of course change the master to dual res. HOWEVER, and this is a big HOWEVER, your drum brake booster WILL NOT have enough power to fully energize disc brakes.
YOU MUST CHANGE THE BOOSTER to a disc brake booster.
This is becoming a repetative rant with me.... There will be those that tell you that the drum booster is adequate. Well, it may be adequate for normal braking, but when do brake let you down? When you need them...
So, when that little kid rides their bike out in front of you, or the idiot in front of you stops unexpectedly - do you want to stop the 12 feet shorter that the disc booster could afford you, or the 12 feet later that is the limit of the old-not-quite-enough-power-drum booster which winds up having you kill that kid or paste your car into the person in front of you?
Think about it. The factory did, and that's why there's two boosters.
Don't skimp out on brakes. Use the correct booster.
I ordered everything. Nothing fits. My car has 1/4" brake lines front to back. The 67 master cylinder has oddball size for the brake lines. The inline tube adapter if bolted to the stock location is no where near correct. I'm dealing with an original 41k mile car. Makes no sense. So it's getting a new booster and a single pot master cylinder. No one died in the first fifty years I'll run it. Absolute frustration from the get go on an "easy" conversion.
Sometimes there are odd-ball arrangements out there that we've not heard of. I can honestly say I have NEVER heard of 1/4" brake lines front to rear on a Mopar... there is a 1/4" line coming out of the single pot master to the distribution block on the front subframe rail, but they usually reduce to the standard size coming out of the block.
Joined: Wed Aug 11 2010, 10:15AM
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DuaneBallard wrote ...
I ordered everything. Nothing fits. My car has 1/4" brake lines front to back. The 67 master cylinder has oddball size for the brake lines. The inline tube adapter if bolted to the stock location is no where near correct. I'm dealing with an original 41k mile car. Makes no sense. So it's getting a new booster and a single pot master cylinder. No one died in the first fifty years I'll run it. Absolute frustration from the get go on an "easy" conversion.
I changed the single reservoir master cylinder on my 64 Imperial to a dual reservoir master cylinder a couple of years ago. I ran the brake line that goes to the rear brakes directly to the front port of the master cylinder using the correct adapter purchased from NAPA.
I purchased another adapter which allowed me to connect the original factory distribution block to the rear port of the master cylinder. The original distribution block has four ports, one in and three out not that that makes any difference. I left the lines to the front brakes untouched and plugged the extra port.
I would have guessed that you had 3?16" brake lines but regardless, the key to doing it this way is getting the correct adapters for your application. The ones that I needed were available from NAPA or you may be able to make what you need. It is not that difficult.
This is an easy conversion which you can do for about $20 plus the cost of the new master cylinder.
Joined: Thu Oct 13 2005, 08:23PM
Location: Beautiful Down Town Roebuck Ontario
Posts: 227
DuaneBallard wrote ...
I ordered everything. Nothing fits. My car has 1/4" brake lines front to back. The 67 master cylinder has oddball size for the brake lines. The inline tube adapter if bolted to the stock location is no where near correct. I'm dealing with an original 41k mile car. Makes no sense. So it's getting a new booster and a single pot master cylinder. No one died in the first fifty years I'll run it. Absolute frustration from the get go on an "easy" conversion.
Got a picture of these parts you ordered? Who did you order them from? It wouldn't be the first time someone was shipped the wrong parts.
I converted my 66 New Yorker and I can assure you it didn't have 1/4" lines on it anywhere. 3/16 IIRC from the single master to the block and 1/8" from there.
I made my own dual line kit from brake lines and adapters you can get at any parts store.
I removed the line to the rear brakes from the distribution block and plugged the port.
I connected the line from the large reservoir for the front brakes to the distribution block and connected the rear brake reservoir to an adjustable proportioning valve and coupled it to the rear brake line.
Done.
If for whatever reason the car does have 1/4" plumbing on it, verify that you have the right parts and use 1/8 to 1/4 adapters where required and adjust the tubing lengths to fit.
Joined: Sat Jan 21 2012, 11:04AM
Location: East Coast
Posts: 58
How many of you out there are running their car everyday with the single reservoir master, 4 drums, and the reflexes of a cat?? And do you have "insurance"? haha
Joined: Sat Aug 19 2006, 05:03PM
Location: Ontario, Canada
Posts: 2919
For disc brake conversion on one of my Chryslers I plumbed it exactly as Kevin (Twostick) describes. For my other one, which I just converted to a dual-res master but kept the drum brakes, no proportional valve needed but the plumbing is otherwise identical.
IMO, the conversion to dual reservoir MC is easy enough that there's little reason not to do it. The only tricky part was finding the right part numbers to adapt the standard brake line fittings to the oddball sizes in the MC ports. Weatherhead makes the required fittings.