Page 1 of 1

Different master cylinder ?

Posted: Sat Mar 04, 2017 12:48 pm
by flammulator
Hello from germany,
I need a new master cylinder.
1970 D200,383,power brakes.
I want to order it by Rockauto.
All the MC that will fit for my car are bolted on with 2 screws, bore 1,125 or bigger.

My one is bolted on with 4 screws and it's bore is 1".
These small ones i can find in trucks with the small block.

Whats wrong?

Re: Different master cylinder ?

Posted: Sat Mar 04, 2017 8:42 pm
by MadMC63
I read on this forum where a gentleman used one from a 72 with no problems. Said it was a bolt on with no mods.

Re: Different master cylinder ?

Posted: Wed Apr 12, 2017 1:41 pm
by moparbay
you can find the 4 bolt 1" bore master cylinder of you look under 1968 d100 w/383. Not sure why that is not listed for the 69-71. It might be that your current setup is not factory and some PO replaced the vacuum booster and master cylinder from an older truck??? I am by no means an expert historian on these trucks. I have always understood that the master cylinder for 4 wheels drums that has a bore of 1" was for manual brakes and the larger bores were for the power brakes. Smaller bore has more pedal travel but requires less effort where as a larger bore has less pedal travel but requires more effort, all things being equal that is.

Re: Different master cylinder ?

Posted: Wed Apr 12, 2017 8:31 pm
by Conrad
I ended up going back to eBay for an NOS item as I couldn't find one that I trusted would work. There are rebuilt A1Cardone master cylinders matching your description that will likely ship international.

I cross-referenced the part numbers and bought an 'NOS' rebuilt MoPar unit on eBay that was for late 71-73 Newport w/power front disc, as the part # matched what was used on the truck for 72-73. It was inexpensive. I'm now looking for a matching 4 post booster.