Topic: 1966 Master Cylinder

[Building 3]

Can anyone tell me if either of these are the correct master cylinder for a 1966 Dearborn built Mustang? Thanks

[CharlesTurner]

Originals were usually Bendix, if you flip them over, there will be markings.  I've seen date codes cast into the bottom and the 'B' logo for Bendix.

[Building 3]

No such luck. The booster has no markings or logos and the master says: Made in USA    45466

In addition to looking for the B and the date code should I be looking for one with the boss that was formerly used for the stop light switch on the top of the housing, on the bottom, or both. In looking through piles of these I have seen all three variations. I am pretty sure the manual brake cars had the boss only on top, but how about the Power Brake system. That's what I am looking for. Thank you.

[CharlesTurner]

Doesn't look like an OEM piece.  The boss for the brake switch carried over into production, some with no hole and some with a hole and plug.

[Building 3]

Thank you. I will keep looking.

[66RavenGTCoupe]

Please correct me if I am wrong guys but I think that this may be what you are looking for

[CharlesTurner]

That's a good example.  The Bendix logo can vary in size.  That one has a julian casting date.

[Building 3]

Charles/RavenGTCoupe: Thanks for the excellent photos.  They help out a lot. Can I assume that for 1966, the unused stop light switch boss is always on the bottom for a power brake car and on the top for a manual brake car? So I need to find one on the bottom for my power brake car. Is there another way to tell the difference? Is the bore size indicated anywhere on the casting? 1" for manual and 7/8" for power? Thanks.

[Building 3]

In trying to track down an original 1966 Power Brake Master Cylinder I need to look for the "B" for Bendix. Also, should I be looking for only ones with the unused stoplight switch boss on the top or doesn't it matter if it's on the top or the bottom?  Will the bore size of 7/8" or 1" always be indicated on the casting? Thank You.