The availability and cost of gasoline meant the weight and the fuel consumption of the 3rd generation had to be considered in the design. In F-body development, both the third generation Firebird and Camaro were proposed as possible front wheel drive platforms, but the idea was scrapped. The state of the art of computerized engine management was in its infancy, and as long as saving fuel was the primary objective, it was not possible to have high horsepower and torque numbers. They did manage to cut enough weight from the design so that acceleration performance would be better than the 1981 models. They also succeeded in the fuel consumption department, offering a 4-cylinder Firebird that would provide 34 miles per gallon. GM executives decided that engineering effort would best be spent on aerodynamics and chassis development. They created a modern platform, so that when engine technology advanced, they would have a well-balanced package with acceleration, braking, handling, and aerodynamics. For the time being, they would have world class aerodynamics and handling, and excellent fuel economy.
The Firebird and Camaro were completely redesigned for the 1982 model year, with the windshield slope set at 62 degrees, (about 3 degrees steeper than anything GM had ever tried before), and for the first time, a large, glass-dominated hatchback that required no metal structure to support it. Two concealed pop-up headlights, a first on the F-Body cars, were the primary characteristic that distinguished the 3rd Gen Firebird from its both its Camaro sibling and its prior form; (a styling characteristic carried into the 4th Gen's design). In addition to being about 500 lbs (227 kg) lighter than the previous 2nd Gen design, the 3rd Generation Firebird was the most aerodynamic product GM had ever released. Wind tunnels were used to form the new F-Body platform's shape, and Pontiac took full advantage of it. The aerodynamic developments extended to the finned aluminum wheels with smooth hubcaps and a functional rear spoiler.
- EFI V6 [RPO LB8] (1985–88): Overhead valves. Cast-iron block. Displacement: 173 cid. Bore & stroke: 3.5 x 3.0 in. Compression ratio: 8.9:1. Brake horsepower: 135 @ 5100 rpm. Torque: 160–165 ft/lbs @ 3600 rpm. Fuel system: Electronic multi port fuel injection. Standard in Firebird S/E. Optional in base Firebird. Not available in Trans Am. Available with 4-speed automatic transmission in base 1987 Firebird.
- 305 V8 [RPO LG4]: Overhead valves. Cast-iron block. Displacement: 306 cid. Bore & stroke: 3.74 x 3.48 in. Compression ratio: 9.5:1. Brake horsepower: 155 @ 4200 rpm. Torque: 240 ft/lbs @ 235–245 ft/lbs @ 2000-2400 rpm. Carburetion: 4-barrel Rochester E4ME. Standard in Trans Am. Optional in base Firebird and Firebird S/E.
- V8 [RPO LB9] (1985–87): Overhead valves. Cast-iron block. Displacement: 306 cid. Bore & stroke: 3.74 x 3.48 in. Compression ratio: 9.5:1. Brake horsepower: 165 @ 4400 rpm. Torque: 235 ft/lbs @ 2000 rpm. Induction: Multi-port fuel injection. Available with 5-speed manual transmission in Formula or Trans Am. Available as a delete option in the Trans Am GTA.
- 350 V8 [RPO L98] (1987): Overhead valves. Cast-iron block. Displacement: 350 cid. Bore & stroke: 4.00 x 3.48 in. Compression ratio: 9.5:1. Brake horsepower: 210 @ 4000 rpm. Torque: 315 ft/lbs @ 3200 rpm. Induction: Tuned port fuel injection. Includes roller valve lifters, a hardened steel camshaft, dual cooling fans, a low-profile air-induction system with aluminum plenum and individual tuned runners. Limited-interim availability as base engine in the Trans Am GTA; optional in Formula Firebird and regular Trans Am.