30dodgeboy,
I hope not to alarm you, but are you aware the very newest those Avon's could be is 35 years old. Once an Avon rep saw a SoCal dragster builder was using their light weight motorcycle/ moped tires on 200+mph dragsters they freaked and went back to England and destroyed the molds. I tried to buy the molds but got a big NO.
So look closely at your Avon's, look for cracks in the tread and sidewall, there is a good chance they are cracked, and hard.
I, Hayden Wheels, sell some Avon tires, but ONLY for show/ cackle cars, NOT for racing. We do sell new Avon "looking" rib tires that are not old.
If you have any questions, feel free to call 800-624-3803
Jon Hansen