240z Master Cylinder Help

[JeffYoung]

I don't think it matters which circuit gets actuated first, but if you switch them buy a cheap line pressure gauge and make sure you get 500-600 lbs or so at the rear drums and 1100+ at the fronts. Easy to do.

I would either remove the stock proportioning valve and plumb in an adjustable or use the one that coorelates to the master cylinder you are using.

[Tom Donnelly]

I actually already have a '73 stock proportioning valve and an adjustable one. And one brand new oem master for a 72+. And 2 good spares. So its beginning to look like its swap time. I wonder if there's an advantage to the early model master though?

And are the calipers and wheel cylinders the same?

Too many dang questions, I just wanna drive.

Tom

[pballance]

I don't think it matters which circuit gets actuated first, but if you switch them buy a cheap line pressure gauge and make sure you get 500-600 lbs or so at the rear drums and 1100+ at the fronts. Easy to do.

I would either remove the stock proportioning valve and plumb in an adjustable or use the one that coorelates to the master cylinder you are using.

+1, I am by no means a hydraulic expert but it shouldn't matter.

The replacement cylinder should be marked, as the oem, with F for front and R for rear circuitry. There should also be a bore size marked on the cylinder. 7/8" covers up to the ZX's I think and they went to a larger bore.

Remove the OEM distribution/proportioning valve and plumb straight to the brakes. Install a in car bias valve for the rear brakes, driver accessible, and make sure the parking brake and cable assembly is installed. Use the parking brake to adjust the rears when the pedal starts getting soft during a race.

good luck, and make sure you have cooling ducts to the fronts, at least 2

just saw your update:
Wheel cylinders are not the same depending on the year. Later ones are easier to come by. Calipers are the same.

[Tom Donnelly]

Where's a good place to get an emrgency brake cable? And for that matter the whole emergency brake system.

[pballance]

I'll look this week and see If I have a spare brake mechanism and relay set up. Cables are tough. OEM are ~ $250 IIRC. I found a new manufactured reproduction on ebay for about $100 shipped to the house. I recall seeing some on ebay recently along with the brake assembly as well.

[Tom Donnelly]

Maybe we can trade out spares. You need anything?

[spawpoet]

Tom,
If Paul doesn't have an e-brake mechanism/cable I would bet we have one in our pile of parts (full warehouse of datsun stuff), and if not we have a parts car that definitly has one. Let me know if you're interested. [email protected].

chris

[Tom Donnelly]

(full warehouse of datsun stuff),

A racer's dream. A warehouse full of spares. That's cool. I have a basement 1/4 full of spares. It goes fast though.

[mom'sZ]

Tom:
Glad you have new OEM because I've seen and heard of a boutload of cheapy rebuilt masters being bad right out of the box.

[Tom Donnelly]

Tom:
Glad you have new OEM because I've seen and heard of a boatload of cheapy rebuilt masters being bad right out of the box.

I've heard that too. I guess that's why NAPA has them for $59.00.