1987
The Firebird body remained basically unchanged. All center, high-mounted stop lamps were relocated to a new position between the spoiler and the rear deck lid, and the large Firebird hood emblem disappeared forever. All V8's now received factory roller camshafts, and faced with consumer demands for more power, GM officially released the new 5.7L with tuned port fuel injection. Available only with an automatic transmission, it produced 210 hp and takes the top performance seat from the 5.0L TPI. L69 production is stopped, leaving the LG4 as the only remaining carbureted V8 used in the F-body. Trans Am GTA (Gran Turismo Americano) was introduced, available with the LB9 305 TPI engine (which was returned to 215 hp) or the L98 350 TPI. Gold 16-inch, flat-mesh, diamond-spoke wheels were standard on GTA, with 16-inch, 20-slot wheels standard on Trans Am.
Firebird Formula was re-introduced, available with a choice of V8's (LG4, LB9 305 TPI, or L98 350 TPI), 16-inch convex wheels, and the earlier Trans Am "Turbo Bulge" hood. The wrap-around wing was updated and now standard on Trans Am and Formula; the regular, flat-surfaced spoiler from earlier Trans Am models was now made standard on Firebird. Trans Am and Formula were also offered with an optional 140 mph speedometer.
WS6 was standard equipment on the Formula and GTA from 1987 to 1992, and optional on the Trans Am. WS6 from 1987 thru 1992 included 36 mm front sway bars, 24 mm rear sway bars, high-speed steering box, gas filled struts and 16" Wheels with 235/50R16 Tires. Later WS6 cars used ZR rated tires.
The Trans Am GTA was Pontiac's pride and joy with a standard 5.7L 350 Tuned Port Injection (TPI). Many people like to say, incorrectly, that the engine itself was pulled directly out of the C4 Corvette, which itself began using the engine in 1985, but the heads on the Corvette were aluminum whereas the Firebird heads were cast Iron, although it did give the GTA performance numbers comparable to GM's flagship performance platform from whence it came. The GTA came with a standard TH-700R4 (4L60) automatic transmission, A/C, new seats with inflatable lumbar and side bolsters, special door panels, epoxy-filled emblems, body-colored ground effects, a special GTA horn button, and the legendary WS6 performance handling package. All of these options were packaged into the Trans Am under the RPO code Y84, and the model was produced until the end of Third Generation F-body production in 1992.
Dealerships could finally order a Firebird Convertible from a recognized coach builder that was already converting other GM products (though more than a dozen other companies had been converting F-bodies into convertibles since 1982 for Pontiac & Chevrolet dealers). ASC (American Sunroof Company, Later "American Specialty Cars") (of ASC McLaren fame) offered Pontiac Dealerships a Firebird/Formula/Trans Am/GTA convertible. ASC was contracted to convert all of the official Camaro Convertibles from 1987 to 1992. However due to fuel economy restrictions mandated by the EPA, a convertible Firebird would have been assessed a $1200 Gas Guzzler Tax because the LB9 & L98 when paired with a Trans Am or GTA would have been lower than 22.5 average MPG. For this reason Pontiac did not directly offer a convertible through dealers like the Camaro. Because these were not an official Pontiac offering, they are considered coach convertibles. The conversion of the Firebird was identical to the "Factory" Camaros of the same model year. The exception was the obvious cosmetic changes, the rear quarter caps, spoiler (Which was a Base spoiler Wing cut off) and the high mount 3rd brake light were Firebird convertible specific.
To order a Firebird Convertible the dealership would order a T-top Firebird and have it Drop shipped to ASC, One Sunroof Center, Southgate, MI 48195 for the conversion along side "Factory" Camaros. Once complete, ASC would ship the now Firebird convertible to the participating dealership for delivery. This remained the procedure for dealerships through the 1989 model year. According to ASC they did not convert any Firebirds for the 1990 model year. As popularity increased and car became lighter & more aerodynamic for the 1991 model year the process was simplified as Pontiac offered a convertible through normal dealer ordering channels via RPO's. A Total of 173 Firebird Convertibles were reported by ASC for 1987.
The 2.8l V6 had very close to the same horsepower as the 5.0l v8 305cid but was a slight difference in torque.
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