I got this information off of the PBR website for replacement brake parts.
I need a master cylinder that will work with a set of 120Y front disc brakes and 1200 rear drums. The car is a 1973 auto 1200 sedan but I can't figure out which master cylinder to order, here is the list.

ACTUATION Brake M/Cyl - Suit: 03/1974 - 12/1976 17.46 mm DISC/DRUM W/O MVAC JB1196

ACTUATION Brake M/Cyl - Suit: 01/1975 - 12/1977 19.05 mm DISC/DRUM WITH MVAC JB1181

ACTUATION Brake M/Cyl - Suit: 01/1977 - 03/1979 19.05 mm COUPE SEDAN DISC/DRUM PBR ORG P7217

ACTUATION Brake M/Cyl - Suit: 01/1978 - 03/1979 19.05 mm ALL BODY TYPES DISC/DRUM JB1172#(NLA)

ACTUATION Kit-B M/Cyl (Min) - Suit: 03/1974 - 12/1976 17.46 mm DISC/DRUM W/O MVAC K7605X#(NLA)

ACTUATION Kit-B M/Cyl (Min) - Suit: 03/1974 - 12/1976 17.46 mm DISC/DRUM W/O MVAC K7859X

ACTUATION Kit-B M/Cyl (Min) - Suit: 01/1975 - 12/1977 19.05 mm DISC/DRUM WITH MVAC K7606X

ACTUATION Kit-B M/Cyl (Min) - Suit: 01/1975 - 12/1977 19.05 mm DISC/DRUM WITH MVAC K7860X

ACTUATION Kit-B M/Cyl (Min) - Suit: 01/1977 - 03/1979 19.05 mm COUPE SEDAN DISC/DRUM PBR ORG K7627X#(NLA)

ACTUATION Kit-B M/Cyl (Min) - Suit: 01/1978 - 03/1979 19.05 mm ALL BODY TYPES DISC/DRUM K7606X

ACTUATION Kit-B M/Cyl (Min) - Suit: 01/1978 - 03/1979 19.05 mm ALL BODY TYPES DISC/DRUM K7860X

ACTUATION Kit-B M/Cyl (Alt) - Suit: 03/1974 - 12/1976 17.46 mm DISC/DRUM W/O MVAC K7638X

JB1196 is for disc front with no booster 11/16"
The pushrod is seperate to the master and stays on the pedal when the master is removed

JB1181 and JB1172 are the same thing 3/4"
They suit boosted system
This would be your minimum master to use

I'd probably step up to the Sunny master JB1289 which is 13/16"

The P7217 is PBR ADR stle unit with the big recatangular bottle.

is there much difference in piston bore size from the 120y to the 1200 coupe calipers, i would have thought the 11/16 would suit? do u need a larger m cyl for disc / disc? i'm running the 13/16, but with twin sumi's and R31 rears, and i only have about 10mm of movement before the pedal is hard? i'm running no booster

Quote:

You can run a 4 pot front with a 2 pot rear with a 7/8 tandem master cylinder without a booster so you should be fine.

Both run same 48mm pistons

would the JB1289 fit into the 1200? and would the 1200 brake lines bolt up to it ok? would there be any modifications needed to fit the unit?

the largest sunny MC works fine with wilwood 4 pots and the rear drums.

i think all the hardlines are the same.

Yes
Yes
No

i agree with killer1200, talk to craig at mad dat, he has the know how...

i agree with killer1200, talk to craig at mad dat, he has the know how...