Datsun Roadster Dual Brake Master Cylinder

[Wikket77]

Hello,
I was wondering if a Dual Brake master Cylinder from a 1968 1600 roadster fit my 1966 1600?
Well this help the braking on the current setup?
Thanks..

[FergO2k]

Now that is an unusual one.
No, it won't be compatible with the brake system in your '66. Plus, the later cars had a pocket cut into the firewall to allow for the lnoger m/c, so a double will probably hit the carbs and possibly the hood.

The dual circuit master cylinder (m/c) means it is looking for 2 brake lines on the car, and your '66 only has one line that feeds over to the junction block, then 2 fronts and one rear departing from the block. (and has one pressure switch, for the S light on the dash).

Dual circuits don't help with stoppping power, they just make you have something left braking wise if there is a fluid pressure loss. (meaning if you have a sudden leak, which is rare, only the fronts OR backs drain and are inop, not a total inop condition).

Single circuit brakes are common, and can be made to work plenty fine.

[ppeters914]

Simple answer is 'No.' You cannot fit the later dual-reservoir brake master cylinders on the earlier cars without hitting the carbs and/or air cleaner.

[fj20spl311]

Simple answer is 'No.' You cannot fit the later dual-reservoir brake master cylinders on the earlier cars without hitting the carbs and/or air cleaner.

UNLESS you have an engine swap.

It will fit, but as Furgus said, you will need to run a short new line to connect to the rear brakes and plug the fitting in the connector where you were disconnected the rear line.

[Wikket77]

Thanks for the commenting.. now I don't have to waste my time taking the other one apart..

[ppeters914]

Simple answer is 'No.' You cannot fit the later dual-reservoir brake master cylinders on the earlier cars without hitting the carbs and/or air cleaner.

UNLESS you have an engine swap.

That's why I said simple. I don't think engine swap are simple for most folks.

[scotty]

I know this is an old thread, but couldn’t you swap the air filters out for 2 pod types and have enough room to run the later model dual master cylinder?

[theunz]

No, it’s not the filter that’s the problem. Your brake lines will need to be modified to work with a 2 cylinder system. It can be done, but it’s not a simple mod. Also, as Fergus mentioned earlier there is the possibility of hitting the hood. There are workarounds, but they are not simple either.

[scotty]

Hitting the hood is a major problem. I wonder if anyone has figured out if there is a double plunger master cylinder that will fit in there, without hitting the hood?

[scotty]

My brakes completely failed the other day, like the pedal went to the floor and I rolled through a stop sign. I’m going to try and figure out how to get a dual- plunger in there without hacking the firewall or welding anything, I just figured someone may have already embarked on this journey.

[msampsel]

I believe I’ve seen Tilton make firewall systems work on older roadsters. Maybe it was Michael Anderson’s post, not sure

[msampsel]

RCMike has a post on Tilton.

[ZeroNilNada]

I did a Tilton swap from a single circuit master to a dual cylinder master on my '66 low windshield car. Took some firewall modification, a new pedal box, cutting out the old pedal supports, a couple of custom brackets, some doublers, and re-routing the brake lines but it works really well. I also did the Spriso big brake upgrade at the same time.

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[redroadster]

I'd recommend trying to rig a frt and rear brake master ...to scary on a single , be sure you have a very good E brake.
also the twin cyls pressure izes the rears 1st then frt brakes. harbor freight s double flair tool and a cheap radius bending tool and practice , the double flair has to be just right

[ZeroNilNada]

I guess my write up wasn’t clear. Definitely two masters, one front, one rear. The pedal has a bias bar built in to allow adjustment front and back. There is a third master for the clutch.