Drew is right, by the mid 80's leaded gas was hard to come by at service stations in most major metropolitan areas. However, the total ban on leaded gas didn't acutally take place until 1996:
EPA Lead Ban

But this ban only applies to pumps providing 'automotive' fuels. It is still legal to this day to produce leaded gas for use in aircraft, race cars and in marine engines. For example, VP's C series fuels are all leaded:
VP Racing Fuels

and legal under the EPA 211n restricted use clause:
"Section 211(n) bans the use of gasoline containing lead or lead
additives for use as a motor vehicle fuel but does not restrict other
potential uses of gasoline containing lead or lead additives. The
definition of motor vehicle is limited to self-propelled vehicles
designed for transporting persons or property on a street or highway.
42 U.S.C. 7550(2). The regulations of 40 CFR Part 80, which are amended
by this rule, apply only to fuel that is sold for use in motor
vehicles. See 40 CFR 80.2(c). The petroleum industry may continue to
make and market gasoline produced with lead additives for all remaining
uses, including use as fuel in aircraft, racing cars, and nonroad
engines such as farm equipment engines and marine engines, to the
extent otherwise allowed by law."

Many guys carried plastic adapters to neck down the larger diameter leaded pump nozzle to fit into the smaller unleaded restrictor filler necks. This was great in places where there were no tail pipe tests, cause one could run cheaper 'Regular' gas. But the lead in the gas ruined the catalyst in the Converter - so as soon as the car found it's way into a metro area where tail pipe tests where enforced, the owner faced an expensive cat replacement. A real concern back then when buying a used car.

regards,
stock49

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