I was looking at a '69 Z today and trying my best to determine if its a real Z/28 or not. I've spent a lot of time on this board and bought the J. MacNeish book on Z/28s but still have a few loose ends.

The original motor is gone, and its an LOS production car. It has the front disk brakes, rear brakes are drums. I looked and unless I was blind I cannot see any casting numbers on the passenger side of the master cylinder. I did take this picture:

http://www.systemtools.com/images/pb.jpg

I've seen other m. cylinders, but this one looked different than others I have seen. What I can't get good information about is the valves and other components underneath the M.C. and attached to the booster.

I did manage to get a '920?' off of the back of the tab on the top of the brake booster, so presumably this would be the '9204' that should be there.

My assumption is that even if someone were to have replaced the motor, they probably would leave the brake systems alone...

Any input is appreciated.

Thanks

Everything appears correct except the master cylinder. It's a replacement. Should be a '309 (last 3 digits).

My 68 Z28 had a MC just like that. I was told that was a common replacement MC. No one really cared when these cars were newer. Just like a car you drive today, something goes bad, you go to an auto parts and replace it.

The part under the MC is a distribution block. The one at the rear is a metering valve. It holds off pressure to the rear brakes until 30#'s or so of pressure is reached.