how difficult and costly would it be to put air conditioning in a 1981 camaro 3.8l that did not come with it?

Answer 1

I'm an a/c tech. It would be costly for the labor alone not including the a/c system unless you got real lucky and came across someone parting out a 1981 camaro with either factory or after market a/c in it. Then you could swap the entire system form car to car. good luck

Answer 2

It would be cheaper and easier to buy another Camaro with air. You can check the site for ideas on cost and what needs to be done to fit a system in your car.