Pontiac Firebird (second generation)
The second-generation debut for the 1970 model year was delayed until February 26, 1970, because of tooling and engineering problems; thus, its popular designation as a 1970½ model, while leftover 1969s were listed in early Pontiac literature without a model-year identification. This generation of Firebirds were available in coupe form only; after the 1969 model year, convertibles were not available until 1989. Models Special/Limited Editions and appearance packages Replacing the "Coke bottle" styling was a more "swoopy" body style, while still retaining some traditional elements. The top of the rear window line going  almost straight down to the lip of the trunk lid, a look that was to epitomize F-body styling for the longest period during the Firebird's lifetime. The new design was initially characterized by a large B-pillar, until 1975 when the rear window was enlarged. 1970. There were two Ram Air engines for 1970: the L74 Ram Air 400 ( in the GTO) and the LS1 Ram Air IV ( in the GTO) that were carried over from 1969. The difference between the GTO and Firebird engines was that the secondary carburetor's throttle linkage had a restrictor which prevented  the rear barrels from opening completely, adjusting the linkage could allow full carburetor operation resulting in identical engine performance. For the 1970 and 1971 model years, all Firebirds equipped with radios had the antennae mounted "in-glass" in the windshield. 1971. The Pontiac engine first became available in the second generation Firebird in 1971. The 455 engine was available in the L75 version and the LS5 335 hp HO version, which was the standard, and only engine option, for the Trans Am. The HO engine also included Ram Air IV. 1972. During a 1972 strike, the Firebird (and the similar  F-body Camaro) were nearly dropped. Again the 455 HO was the only engine available for the Trans Am. Starting in 1972, and continuing until 1977, the Firebird was only produced at the Norwood, Ohio, facility. 1973. In 1973, the Trans Am added two new colors to the Cameo White, Buccaneer Red and Brewster Green. Other exterior upgrades included the revised nosecone Firebird decal and the new, soon to be iconic, hood bird decal. This option (RPO WW7) was a pay extra $55 option exclusive to Trans Am. The "Trans Am" decals were slightly larger than previous versions, and  shared the same color schemes as the hood decal. Inside the Firebird the standard interior equipment was almost identical to prior years. The new "horse collar" optional custom interior featured new seat coverings and door panels. Interior colors were limited to black, white, burgundy and saddle but orange, red and blue carpet could be specially ordered to any of the combination. The 1973 model line introduced "radial tuned suspension" for the Trans Am. When ordered, it included the 15-inch radial tires. Radial tuned suspension with radial tires delivered a much more comfortable ride, while providing improved cornering grip. Radial  tires where just coming onto the market and Pontiac's engineering department then implemented RTS as a standard feature for the Trans Am model line. The Firebird also had to meet the new safety and emissions requirements for 1973. There were now extra steel reinforcements in the bumper and core to support the fender. All Pontiac motors now had to be fitted with new EGR system, which delayed the SD-455 Program until late into production year. The 1973 Trans Am engine displaced 455 cubic inches, with the two options being the base L75 and Super Duty LS2. The base 455  produced 40 fewer horsepower than the round port Super Duty 455. Horsepower for the base L75 455 was rated at 250 at 4,000 rpm and 370 lb/ft at 2,800 rpm. Pontiac removed the "HO" designation from the base engine, and simply labelled the now non-functional shaker with "455". In 1973 and 1974, a special version of the 455, called the "Super Duty 455" (SD-455), was offered. The SD-455 consisted of a strengthened cylinder block that included four-bolt main bearings and added material in various locations for improved strength. Original plans called for a forged crankshaft, although actual  production SD455s received nodular iron crankshafts with minor enhancements. Forged rods and forged aluminium pistons were specified, as were unique high-flow cylinder heads. These motors wore the "SD-455" shaker callout and also featured a decal on the driver's side valve cover with oil specifications. These "hand assembled" engines were developed to withstand aftermarket modifications and operate at a higher RPM range when contrasted with the L75. Horsepower for the LS2 SD-455 was rated at 290 at 4,000 rpm and 395 lb/ft at 3,600 rpm. The 1973 Trans Am production was up over previous years, the L75 455  production had 3,130 automatics and 1,420 manuals. The special ordered $550 option LS2 SD-455 production had 180 automatics and 72 manuals. The 480737 code cam (identical grind to the RAIV "041" cam) was originally specified for the SD455 engine and was fitted into the "pre-production" test cars , one of which was tested by both "Hot Rod" and "Car and Driver" magazines. However, actual production cars were fitted with the milder 493323 cam and 1.5:1 rocker ratios, due to the ever-tightening emissions standards of the era. This cam and rocker combination, combined with a low compression ratio of  8.4:1 advertised (7.9:1 actual) yielded 290 SAE net horsepower. Production SD455 cars did not have functional hood scoops, while the "pre-production" test cars did. McCully verified that no production SD455s released to the public were fitted with the 480737 cam. When asked about the compromises for the production SD455 engine, McCully responded, "Compression, camshaft, jetting, and vacuum advance". He followed by stating that he would have preferred a compression ratio of 10.25:1, a camshaft with 041 valve timing, slightly richer carburettor jetting, and as much vacuum advance as the engine would tolerate. However, that proved to be impossible due  to the emissions regulations of the era. 1974. Curb weights rose dramatically in the 1974 model year because of the implementation of telescoping bumpers and various other crash- and safety-related structural enhancements; SD455 Trans Ams weighed in at in their first year of production (1974 model year; actually 1973). The 1974 models featured a redesigned "shovel-nose" front end and new wide "slotted" taillights. In 1974, Pontiac offered two base engines for the Firebird: a inline-six and a V8. Available were V8 engines, as well as the produced , while the SD-455 produced . The 400, 455, and SD-455 engines  were offered in the Trans Am and Formula models during 1974. A June 1974 test of a newly delivered, privately owned SD-455 Trans Am. This appeared in "Super Stock and Drag Illustrated". With an unmodified car and a test weight of 4,010 lbs the testers clocked 14.25 seconds at 101 mph. The car had an automatic and A/C. Also, the factory rating of 290 hp was listed at 4,400 rpm while the factory tachometer has a 5,750 rpm redline. A production line stock 1974 SD455 produced 253 rear wheel HP on a chassis dyno, as reported by "High Performance  Pontiac" magazine (January 2007). This is also consistent with the 290 SAE net horsepower factory rating (as measured at the crankshaft). A 1974 Firebird was driven by Jim Rockford in the pilot movie and the first season (1974–1975) of "The Rockford Files"; every following season, Rockford would change to the next model year. However, in the sixth season (1979–1980), Rockford continued to drive the 1978 Firebird from season five, as the star, James Garner, disliked the 1979 model's restyled front end. The cars in the show were badged as lower-tier Esprit models but were Formulas with the twin -scoop hood replaced with a scoopless one. Another hint was the twin exhausts and rear anti-roll bars that were not used on the Esprit. 1975. The 1975 models featured a new wraparound rear window that curved out to occupy more of the B-Pillar, but the rear body shape and bumper remained unchanged. The turn signals were moved up from the valance panel to the grills which helped distinguish the 1975 from the 1974 front end as they are relatively the similar. This was also the last year of the larger profile larger snout Formula hood for the Firebird  Formula. The Super Duty engine and TurboHydramatic 400 3-speed automatic were no longer available in 1975. Due to the use of catalytic converters starting in 1975, the TH400 would not fit alongside the catalytic converter underneath the vehicle. The smaller TurboHydramatic 350 automatic was deemed suitable as the power output for the motors had significantly decreased from the earlier years. TH350 drew less power from the motor, and also did not require an electronic kickdown system. The Pontiac L78 400 was standard in the Trans Am and the 455 was optional for both 1975 and 1976 models. Originally, the  L75 455 7.5L V8 was dropped entirely, but public demand saw the 455 return mid-year, available only with a 4-speed Borg Warner Super T-10, and it was no longer available for the Formula. Although it was brought back as the "455 H.O", it was not the same motor as the 1971-72 LS2 455 HO seen in the earlier Firebirds. The motor was a standard D-port engine with a very low profile camshaft and restrictive exhaust system that was also seen in the larger body Pontiac platforms. The power output was restricted to 200HP with a torque  rating of 330 lb⋅ft at 2000rpm. This resulted in a very critical response to the "HO" moniker being used on a station wagon motor by critics at the time. However, when later contrasted to what other performance vehicles were available on the market, it was the largest displacement "performance" motor still available that could easily produce more power with basic modifications. Track testing in 1975 showed the 455 received a 16.12 second quarter mile time, which was on par with the only other competition, the L82 Corvette. 1976. Pontiac celebrated its 50th anniversary year in 1976. To commemorate this event , Pontiac unveiled a special Trans Am option at the 1976 Chicago Auto Show. Painted in black with gold accents, this was the first "anniversary" Trans Am package and the first production black and gold special edition. A removable T-top developed by Hurst was set to be included on all Y82 LE T/As, but proved problematic in installation and quality control, leading some Y82s to not be delivered with the Hurst T-top roof. All Hurst T-top equipped cars were built at the Norwood, Ohio, factory. It became an available option for other Firebirds in 1977. 1976 marked  the end of the Pontiac L75 7.5 liter 455 V8, as it could no longer meet the tightening emissions restrictions and the "HO" moniker used the year prior was dropped. The L75 was only available with a four-speed manual Borg Warner Super T-10, and was exclusive to the Trans Am. 1976 also introduced the "W50 appearance package" for the Formula model line, consisting of a two-tone appearance package with lower accents across the bottom of the body, a large "Formula" decal across the bottom of each door, and a "Firebird" decal on the rear spoiler. 1977. The Firebird  received it's most recognizable front end for the 1977 model year. The shaker scoop was also revised for this year, with the early 1977-built T/As coming with off-center, lower-profile shaker scoops. The Formula hood was changed for the last time for the second generation with a much lower profile. The snowflake wheel became an option for all Firebirds and was standard with the Y82 appearance package, although it could be replaced with Rally II wheels as a credit option. For the Esprit, an optional appearance package RPO W60 called the "Skybird appearance package" became available , featuring an all blue exterior and interior. This package was originally slated to be called the "Bluebird" similar to the "Yellowbird" and "Redbird" packages to follow in the upcoming model years, but the name was already in use for a company that produced school buses. In 1977, General Motors began to source a larger selection of V8 motors to supply in the lower model Firebirds, and the Oldsmobile 350 V8 as well as the Chevrolet 350 V8 became options for the Firebird, Esprit, and Formula. This was the first time GM had required Pontiac to source another V8 motor to  supply in its Firebird model line, as previously, the Chevrolet inline six was the only other outsourced motor seen in a Firebird. This marked the beginning of the end for Pontiac's engine development. The Trans Am had now three different engine options to chose from, the standard Pontiac L78 400, the pay extra Pontiac W72 400, and the Oldsmobile-sourced L80 403. 1977 also saw the cubic inch metrics on the shaker dropped in favour of the displacement of the cylinders. The shakers now wore the decal "6.6 Litre" for all L78 Pontiac 400 and L80 Oldsmobile 403 motors . Only the optional W72 Pontiac 400 received the "T/A 6.6" decal. Many reproduction decal kits for Firebirds often did not include the "6.6 Litre" decal, which is why many Firebirds today bear the incorrect decal on the shaker. As Pontiac had lost the 455 in the previous model year, they offered a modified 400 Pontiac V8 dubbed the "T/A 6.6" RPO W72 with a single four-barrel 800CFM Rochester Quadrajet carburettor rated at at 3,600 rpm and a maximum torque of at 2,400 rpm, as opposed to the regular 6.6 Litre 400 (RPO L78) rated at . The T /A 6.6 equipped engines had chrome valve covers, while the base 400 engines had painted valve covers. For 1977, the W72 shared the same air cleaner as the L78. The Oldsmobile 403 was implemented as the 400 Pontiac could not satisfy emissions requirements for high-altitude states and California. Wanting to still offer a 6.6 litre option for the Trans Am, the 403 Olds was seen as a suitable replacement as when equipped with an A.I.R emissions system, it could satisfy the emissions criteria for these states and still offer the power the Trans Am was known for. The L80  Oldsmobile had slightly more power than the standard L78 Pontiac 400 at 185 hp (138 kW) and offered the same low end torque of 320 lb⋅ft (430 N⋅m) at a more useable operating range of 2,200rpm. From 1977 to 1981, the Firebird used four square headlamps, while the Camaro continued to retain the two round headlights that had been shared by both second-generation designs. The 1977 Trans-Am special edition became famous after being featured in "Smokey and the Bandit". The 1980 turbo model was used for "Smokey and the Bandit II". 1978. Changes for 1978 were slight, with  a switch from a honeycomb to a crosshatch pattern grille being the most notable change to the body style. The decals for the standard Trans Ams changed from the "looping style" lettering to the "block-style" font that would remain on the Firebird until the end of the second generation. T-tops in 1978 transitioned from Hurst units to Fisher (GM) in mid-year. Pontiac also introduced the Red Bird package on the Firebird Esprit model. Painted in Roman red with a matching deluxe red interior, it demonstrated gold accents with a unique Red Bird graphic on the b-pillars . It also included a Formula steering wheel with gold spokes and gold dash bezel, similar to the ones included in Special Edition package, however, the red and gold steering wheel was exclusive to the Red Bird Esprit. The W72 engine option also saw a revision to the camshaft duration and the tuning of the Rochester Quadrajet which lead to a 10% increase of horsepower from the following year, bringing the total to 220 hp. The WS6 special performance package developed by Herb Adams was introduced as a handling option for the Trans Am, including a larger diameter rear sway bar , tighter ration steering box, 15x8 snowflake wheels, additional frame bracing, as well as other suspension changes. Delays in manufacturing prevented the rear disc brake (RPO J65) from being available on the 1978 model year. Approximately 25% of Trans Ams in 1978 had the WS6 option according to Pontiac sales information at the start of 1979. 1979. The front end was restyled for 1979, which also marked the 10th anniversary of the Trans Am. For 1979, there were three possible engine options. The L80 Oldsmobile 403ci motor became the standard motor and was only available with the TH350 3-speed automatic . The W72 was available for a short period and in limited supply. This was the last of the line for the Pontiac large displacement V8 engines, and only available with the Borg Warner Super T-10, also requiring the WS6 handling package as mandatory equipment in conjunction with this driveline choice. As an alternative option for customers who wanted a four-speed transmission, the smaller displacement Pontiac L37 301 4.9 liter V8 was offered as a credit option and could come equipped with either the ST-10 or TH350. A limited-edition anniversary package was made available: platinum silver paint with charcoal  gray upper paint accents and mirrored T-tops, and a special interior featuring silver leather seats with custom-embroidered Firebird emblems and aircraft-inspired red lighting for the gauges. The 10th-anniversary cars also featured special 10th-anniversary decals, including a Firebird hood decal that extended off of the hood and onto the front fenders. Pontiac produced 7,500 10th anniversary cars, of which 1,817 were equipped with the high-output Pontiac T/A 6.6 W72 400 engine. Two 10th anniversary Trans Ams were the actual pace cars for the 1979 Daytona 500, which has been called the race that made  NASCAR. "Car and Driver" magazine named the Trans Am with the WS6 performance package the best handling car of 1979. During period dyno testing, the National Hot Rod Association rated the limited-availability T/A 6.6 high-output Pontiac 400 engine at 260–280 net horsepower, which was significantly higher than Pontiac's conservative rating of 220 hp. In 1979 Pontiac sold 116,535 Trans Ams, the highest sold in a year. 1980. In 1980, ever-increasing emissions restrictions led Pontiac to drop all of its large-displacement engines. 1980 therefore saw the biggest engine changes for the Trans Am. The 301 , offered in 1979 as a credit option, was now the standard engine. No manual transmission was available for the Formula or Trans Am in 1980, all received the 3-speed automatic Turbo Hydramatic 350. Engine options included a turbocharged 301 or the Chevrolet 305 small block. The turbocharged 301 used a Garrett TB305 turbo attached to a single Rochester Quadrajet four-barrel carburettor and featured a hood mounted "boost" gauge that would light up as the TB305 accumulated boost. The hood of the 301T equipped Firebirds had a large offset bulge to accommodate for the mounting position of the  carburettor on the motor as the turbocharger exhaust occupied a large amount of space in the engine bay. The 301T set up was relatively primitive new technology at the time of its development and could not properly maximise the efficiency of the turbocharged set-up. The 301T equipped T/A's were restricted to an automatic transmission and a 3.08 rear differential ratio, but were seen as a disappointment contrasted to the venerable W72 400 available just a year prior. Some owners have claimed quite reasonable performance numbers with the modern fuels. A 1980 turbo Trans Am was  featured in the movie "Smokey and the Bandit II", but was fitted with nitrous oxide tanks by Marvin Miller Systems to get the desired performance. 1981. 1981 became the final year for the second generation Pontiac Firebird. The three engine options were unchanged for the model line-up, however, the option for a four-speed Borg Warner Super T-10 was re-introduced for the Formula and Trans Am, but was only available with the Chevrolet sourced LG4 305 5.0 liter V8. As with all other General Motors vehicles for 1981, all engines came equipped with the "computer command control" system  attached to the carburettor. The hood decal for the 1981 model year was also slightly restyled. All Firebirds also received an embossed silver Firebird decal on the petrol tank cap attached to the rear taillights. On the special edition Trans Ams, this Firebird was gold. The G80 limited slip differential that was previously standard for the last decade on all Trans Ams became a pay-extra option. This decision was made by Pontiac to prepare dealers for the new ordering and pricing for the third generation Firebird where the G80 was no longer being included as a standard option for  the Trans Am.