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Single to dual master cylinder fittings question.


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11:13 AM
Apr 24, 2023
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Hi folks. I've installed a dual res master cyl in my 63 Savoy. I'm having a hard time with the fittings and lines on the master side.
First though, are the new lines from the master going to be 1/4 inch instead of 3/16? Also, the fittings on the master are two different sizes. Looks like the one nearest to the firewall is maybe 1/2 inch and the other is larger, maybe 9/16 inch. I'm thinking that I may need reducers of some kind at the tee block also. I would appreciate any info and pics if possible. Thanks, Wally.
Special fitting so you can't put front and rear lines wrong. You can buy fitting that are correct 3/16" lines. Also adapter fitting to make both 3/16" lines. Front of MCis Rear brakes Rear outlet is for Front brakes. If you buy adapters make sure threads that go into MC are long enough. Bought adapters and they bottomed out before they were seated. Bought longer threaded ones at NAPA.
I just went through this on my 66 Charger. I tried lines with fittings but they wouldn't bottom out. I ended up with adapters to 3/16 lines. I switched to front discs so I blocked off the original 1/4 inch inlet port in the distribution block and ran a 3/16 line from the master to feed the front brakes and ran the rears separately through a proportioning valve.