Dual Cylinder - Master Brake Cylinder

[alpineracer]

Has anyone used this:

http://www.blackdragonauto.com/features/z/ZBMC.htm

I know it is longer than any of the stock cylinders, but came across it when researching for the aluminum rear brake drums the early Z cars used which can be adapted to the Alpine axle hubs.

 

[260Alpine]

The earlier one is 7/8", the later 15/16" bore. You want 11/16" to 13/16" with 3/4" ideal. Another issue is the bottom fittings hit the steering box of the Alpine. May work fine for the Tiger with larger than stock brakes.

 

[PROCRAFT]

Rock auto 7/8" PN 13-1658 39 bucks$ 260/280Z

 

[Barry]

Series Alpines without a brake booster had 0.700" (Series I / II) or 0.750" (Series 3 / IV / V) master cylinders.

Series Alpines with a brake booster had 0.875" (7/8") master cylinders.

There is no practical way to use a tandem master cylinder with a brake booster.

A 0.875" (7/8") master cylinder (tandem or not) on a Series Alpine with stock calipers and without a brake booster will give a very heavy brake pedal.

 

[260Alpine]

Plus, the fittings interfere with the steering box. The Tiger, the master is moved over.

 

[DanR]

There is no practical way to use a tandem master cylinder with a brake booster.

Barry, do you mean when the brake cylinder and the booster are hooked together ? or seperate?

 

[DanR]

I recently obtained a master cylinder very similar to the 64-103 that has the 3/4" bore. I believe it is possible to make it work in one of my 2.8 V6 Mustang II conversions.

I also recently was able to get a Master Brake Cylinder 3/4" bore with the pressure connections on the engine side that I believe also will work. I may have to either remove the brake lines to the master cylinder when and if the valve covers should need to be removed.

 

[Barry]

Barry, do you mean when the brake cylinder and the booster are hooked together ? or seperate?

Sorry, but I don't understand your question.

A tandem MC has two "separate but equal" hydraulic outputs. If you plumb only one of the outputs to a booster, then the series Alpine brake system would be wildly unbalanced. Plumbing the two "separate but equal" hydraulic outputs from a tandem MC to two "separate but equal" boosters would theoretically work, but it is certainly not practical.

 

[DanR]

Barry, I made the question not understanding if the units were linked together inline as in some American cars. I now understand what you said

Anyway, missed you Saturday in Norcross. Had a good showing of the Sunbeams.

 

[Barry]

Barry, I made the question not understanding if the units were linked together inline as in some American cars. I now understand what you said Anyway, missed you Saturday in Norcross. Had a good showing of the Sunbeams.

Dan,

I understand your question now. As you noted, American cars with power brakes mostly used a vacuum powered mechanical booster between the brake pedal and the master cylinder (in an integrated unit). For the series Alpines, Rootes used a normal (un-boosted) master cylinder and then used a separate vacuum powered hydraulic booster between the master cylinder and the calipers / wheel cylinders. Both systems lower the pedal effort to achieve a given hydraulic pressure to the brakes. I assume (yes, I know) that Rootes used the normal MC + separate vacuum powered hydraulic booster because there was not enough room for an integrated mechanical booster + MC in the series Alpine engine bay. Not a matter of better / worse, just a practical solution to the constraints of the very cramped series Alpine engine bay.

Planned on being at Norcross, but out-of-town family issues got in the way. Maybe Hilton Head on 3 NOV???