10" brakes on formula S cars?

My car also came with 13 inch tires on the broadcast sheet.
I found something. I bet your Barracuda was a standard built car with 9" brakes, the Performance group (273 and other goodies) and the Sport Group because you said you had 13" tires. Did you have a 3 spoke sport steering wheel?
Now for the brakes. In the AMA specs there's a chart of what brakes came on what car models. You would probably have to dig on your fender tag and build sheet to confirm your model and the particular brakes you have. I haven't found what the AV1 and AV2 cars are specifically, but if yours was a AV1 it came with 9" brakes standard and 10" optional. The AV2 cars came with 10" brakes standard.

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