Tim, thanks for telling us about your experiences and observations with regard to '68 GT500s.
Some questions to all:
My car was originally purchased by a Dr. in the Lynn, MA area. Sometime after he sold it, or traded it in on a new car, and before I bought it in June 1976, I'm all but certain that this Shelby GT500 Mustang was rode really hard and put up soaking wet more than once. Warranty records I got from Mongo show that the Dr brought it in for warranty work for freon leaks and recharges. At some point, and perhaps off warranty, the C8ZX compressor assembly was replaced with what I currently have, the C9AZ-B labeled compressor and whatever clutch is currently on it. What I don't know is if the larger diameter field coil style clutch was carried over from the original compressor to this replacement compressor labeled C9AZ-B.
Here are 2 pictures of the compressor, with the pulley and clutch attached. Is this the clutch with the large diameter field coil?
...and here's a picture of the ID plate. While I'd like to believe that the compressor assembly may have worked for a while, what does the info on the plate tell us about this compressor and its suitability, from a performance aspect, in a GT500 application?
If the compressor can be used, and the clutch is not the large diameter field coil, can a large diameter field coil be fitted to this compressor?
Why was a large diameter field coil selected for use on GT500s with A/C?
Steve