The fourth-generation Pontiac Firebird arrived in 1993 with a windshield raked at sixty-eight degrees, a small-block borrowed almost intact from the Corvette parts bin, and a concept car in its family tree that never reached production. Over five model years Pontiac kept quietly escalating it, from a 160-horsepower base six to a Ram Air package making 305. Here is what actually changed between 1993 and 1997, and why these are the bargain years.