Generation 4 - 1993-2002

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The Fourth Generation F-body continued the aerodynamic formula initiated by the previous generation, but while still a desirable sports car, it fell victim to declining sales. As before, the Camaro kept the exposed headlights and the Firebird its pop-up units, with some minor changes. The overall styling of the Firebird more strongly reflected the "Banshee IV" concept car than the 1991 "face lift" received by the Third Generation model.

From 1993 until 1995 (1995 non-California cars), Firebirds received a 3.4L V6 with 160 hp, or the 5.7L 275 hp LT1 V8. The 1993 Firehawk (only available in Formula trim for 1993) received the SLP package with a functional hood scoop and other performance enhancements that increased power to 300 hp. Only 201 were built for 1993, and they routinely out-performed 1993 Corvettes, leading many to believe that the power rating was purposely underrated to allow the Corvette (also rated at 300 hp for the 1993 model year) to be the listed "king of power" (and price tag) for that year. In fact, the LT1 in the Formula and Trans Am was very similar to the one in the Corvette C4, except with 2-bolt mains and a more restrictive intake/exhaust system.

1994 marked the 25th Anniversary of the Trans Am, and another Anniversary Edition was released, painted white with a single blue stripe down the center of the vehicle — clearly reminiscent of the 1970 Trans Am. 1995 models were the same as that of previous years, but traction control (ASR: Acceleration Slip Regulation) was now available. A freer intake/exhaust was available similar to that of the Chevrolet Corvette giving 310hp on very few models.


1993-1997 Trans Am Convertible1996 and later models had a 200 hp 3.8L V6 as the base engine, and the power rating of the LT1 had been raised to 285, thanks to a new dual catalytic converter exhaust system which was offered in previous years by order only. The very rare 1997 Firehawk LT4 model made by SLP Performance Parts and sold through Pontiac dealerships had 330 hp (243 kW) and 340 ft·lbff (459 Nm) of torque.


One of 12 1998 Pontiac Trans Ams in factory "Bright Purple Metallic"In 1998, the Firebird received a "face lift" dominated by a new front fascia (now with four pop-up headlights) as well as other modifications, the most significant of which was the introduction of the latest Corvette small block V8 engine, the LS1. Initially, the color "Bright Purple Metallic" had been available, however it was discontinued due to production issues with the paint. The color was replaced with "Navy Blue Metallic," but not before a total of 12 Trans Am models (10 coupés and 2 convertibles) made it out of the factory dressed in "Bright Purple Metallic."[1] For 1998-2002 Pontiac utilized the same heavy duty brakes, steering ratios, fuel pumps and shocks (non-WS6) on both V6 and V8 models.


The 1999 30th Anniversary Trans Am1999 marked the 30th Anniversary of the Trans Am, commemorated by another white Anniversary Edition, this time with twin blue stripes which more closely patterned the original paint scheme of the 1969 Trans Am. The final model year of the Firebird, 2002, offered a distinctive "Collector's Edition" Trans Am, painted yellow. Like the Chevrolet Camaro, the Fourth Generation Firebird and Trans Am were built in Sainte-Thérèse, Quebec, and the plant closed down after producing the last F-body cars.

The LS1 Firebirds, despite their poor sales, were among the fastest ever produced. Outfitted with the all-aluminum 5.7L V8 from the Corvette C5, and producing 305 hp (310 after 2000) or 320 hp (325 after 2000) in the WS-6 "Ram Air" version, these Fourth Generation Firebirds could out-perform just about any of their predecessors (including the original "muscle car" Firebirds). In 2001 and 2002, models equipped with a V8 received the higher-flow LS6 intake manifold and a higher-performance clutch. Firebird enthusiasts believe these engines were underrated by the factory, and that these cars often produce up to 40 horsepower (30 kW) more than rated. The rare Firehawk model, made by SLP and sold through Pontiac dealerships, had 330 hp (335 after 2000, 355 in late 2002 models).

Even the last of the V6-equipped Firebirds were rated at an impressive 205 hp, which was more than some of the earlier-generation V8's could muster (in fact, the final V6 Firebirds are as quick as almost any V8-equipped Firebird produced before 1990). Average quarter-mile elapsed times for the Fourth Generation Firebirds were reported as 15.2 seconds at 90 mph for V6-equipped vehicles, and 13.2 seconds at 110 mph for those with the V8; in the hands of an experienced driver, the latter cars have even been known to "crack" the 12-second quarter mile mark. Top speeds for both the V6 and V8 versions were generally governed according to their factory tire ratings, which were typically 118 mph for the V6 models. However, with the governor programmed out and applying V8 speed rated tires, V6 Firebirds will reach in excess of 130 mph (4th gear limited) with the Y-87 performance package and a 5-speed transmission, whereas V8 models that had Z-rated tires had a speed limiter set to 167 mph.

V6 Firebird

1993-1998 had angular cable driven throttle body units, which later changed in 1999 to a less restrictive drive by wire electronic controlled with 18 reference throttle position points. 1999-2002 also saw the change of mass airflow sensor technology. GM, ridding themselves of the cast rod Mass Airflow Sensor in the Throttle Body, chose the higher flow capacity of the top mount MAF sensor and eliminating the angled induction to a straight forward ram air style intake which removes a large portion of the restriction.

In 2000-2002 Firebird also received an upgraded exhaust manifold from rectangular cast Iron primaries to a round tubular style manifold giving further gains in performance.

Deliberately Underrated Power & Performance

Although all Fourth-Generation Firebird Formulas and Trans Ams are very powerful vehicles, claims abound from owners and aficionados that their true horsepower ratings were grossly underrated by GM. Reasons such as higher insurance rates for potential buyers are cited as affecting the company's decision to conceal the true horsepower output and acceleration times of the vehicles. Another major reason cited for such a deception was potential harm to the sales figures of GM's performance flagship, the Fifth-Generation Chevrolet Corvette. Since the Trans Am and Corvette powertrains were effectively identical (same engine & transmission), GM allegedly kept the Trans Am's true profile and performance numbers from the public. This, in turn, spawned better sales for the higher-priced Corvette even though the true performance figures of the Trans Am were purportedly the same with only minor differences in the ecu programming.

- Courtesy of Wikipedia