1970–1981 Pontiac Firebird / Trans Am / Esprit — Second-Generation Technical and Collector Guide
Historical Context and Development
Pontiac launched the second-generation Firebird in February 1970, reshaping the F-body platform into a lower, wider, more aerodynamically honest fastback coupe. The lineup—base Firebird, Esprit, Formula, and Trans Am—covered luxury to outright performance. Corporate constraints were real: GM’s emissions and insurance headwinds arrived just as the original muscle era was slowing, yet Pontiac’s chassis and engine teams (with influential figures like Herb Adams) leveraged tuning, aerodynamics, and gearing to keep the Firebird competitive throughout the 1970s.
Design-wise, the long-nose/short-deck proportions remained, but the semi-fastback roofline and Endura nose (particularly 1970–73) delivered a visual identity distinct from its Camaro sibling. Functional aero elements on the Trans Am—NACA hood inlets, fender air extractors, spats, and rear spoiler—were not mere styling; they were validated in the wind tunnel and on proving grounds.
Motorsport provided direction if not direct silverware. While factory SCCA Trans-Am efforts peaked earlier, privateers campaigned second-gen Firebirds in A-Sedan/Trans-Am and IMSA, and development offshoots like the Herb Adams Fire-Am program informed later factory options. The WS6 suspension package (introduced for 1978) was a direct response to the handling-first mentality shaping the late 1970s performance landscape, which increasingly valued lateral grip over raw quarter-mile times.
Competition was fierce: Ford’s Mustang II gave way to the Fox-body in 1979; Chevrolet’s Camaro Z/28 tracked closely in power and chassis specification; Chrysler’s E-bodies faded by 1974. Against that backdrop, Pontiac’s insistence on meaningful hardware—W72 400s, the mythic SD-455, and later the turbocharged 301—kept the Firebird relevant and, in some cases, class-leading.
Engines and Technical Specifications
Across 1970–1981, the second-gen Firebird family used a mix of Pontiac V8s (301, 350, 400, 455), the Oldsmobile 403 (1977–79 in many automatic Trans Ams), and Chevrolet small-blocks in select applications/regions. Fuel systems were Rochester two- and four-barrel carburetors, with a draw-through turbo setup for 1980–81. Below are representative powertrains with key technical details.
| Engine (Code/Years) | Configuration | Displacement | Horsepower (rating) | Induction | Redline | Fuel System | Compression | Bore/Stroke |
|---|---|---|---|---|---|---|---|---|
| 400 Ram Air IV (1970) | 90° OHV V8, iron block/heads | 400 cu in (6.6 L) | 345 hp (SAE gross) | Naturally aspirated | ≈5,600 rpm | Rochester Quadrajet 4-bbl | ≈10.5:1 | 4.12 in × 3.75 in |
| 455 SD (1973–1974) | 90° OHV V8, fortified bottom end | 455 cu in (7.5 L) | 290 hp (SAE net) | Naturally aspirated | ≈5,000 rpm | Rochester Quadrajet 4-bbl | ≈8.4:1 | 4.15 in × 4.21 in |
| 400 W72 (1977–1979) | 90° OHV V8, high-output spec | 400 cu in (6.6 L) | 200–220 hp (SAE net, year/gearbox) | Naturally aspirated | ≈5,200 rpm | Rochester Quadrajet 4-bbl | ≈8.0:1 | 4.12 in × 3.75 in |
| 403 Oldsmobile L80 (1977–1979) | 90° OHV V8, thin-wall casting | 403 cu in (6.6 L) | 185 hp (SAE net) | Naturally aspirated | ≈5,000 rpm | Rochester Quadrajet 4-bbl | ≈8.0:1 | 4.351 in × 3.385 in |
| 301 Turbo (1980–1981) | 90° OHV V8 with single turbo | 301 cu in (4.9 L) | 210 hp (1980), 200 hp (1981) (SAE net) | Turbocharged (draw-through) | ≈5,000 rpm | Rochester Quadrajet 4-bbl | ≈7.6:1 | 4.00 in × 3.00 in |
| 350 Pontiac (Esprit, early 1970s) | 90° OHV V8 | 350 cu in (5.7 L) | ≈250 hp (SAE gross, 2-bbl) | Naturally aspirated | ≈5,000 rpm | Rochester 2-bbl | ≈8.8–9.0:1 | 3.875 in × 3.75 in |
Driving Experience and Handling Dynamics
The second-gen’s road feel evolves distinctly across its long run. Early Trans Ams (1970–72) feel mechanical and direct: heavy but communicative steering, short-throw Muncie 4-speeds, and stout Pontiac big-inch torque. The SD-455 cars add an ironclad bottom end and unusual midrange authority—easy pace on the street, surging acceleration when prodded.
The late-1970s cars sharpen handling. WS6 (from 1978) introduced larger sway bars, tighter steering gears, specific springs, 15×8-inch wheels, and performance tires. By 1979, many WS6 cars gained four-wheel discs (J65), giving reassuring, modern-feeling pedal response for the era. W72 400s combine that chassis with credible thrust; even the Olds 403 automatic cars, while softer, benefit palpably from WS6 geometry and rubber.
Throttle response tracks the hardware. Quadrajet secondaries add a progressive, almost binary intensity when the back barrels open; properly tuned, the transition is seamless. The 301 Turbo brings boost-era character—torque arrives in a swell rather than an immediate hit, with the draw-through layout and emissions calibration prioritizing drivability and detonation margin over peak thrust. Gearboxes span Muncie M20/M21 into Borg-Warner Super T-10 (mid-1970s onward) for manuals, and TH350/TH400 for automatics; shift quality is durable and businesslike rather than delicate.
Performance Specifications (Representative)
Period test numbers vary with equipment, gearing, altitude, and test protocol. The following reflects commonly published ranges for stock, well-tuned examples.
| Variant/Engine | 0–60 mph | Quarter-mile | Top speed | Curb weight | Layout | Brakes | Suspension | Gearbox |
|---|---|---|---|---|---|---|---|---|
| 1970 Trans Am 400 Ram Air IV (4-spd) | ≈5.9–6.2 s | ≈14.2–14.6 s @ ~100–102 mph | ≈130–135 mph | ~3,600–3,700 lb | Front-engine, RWD | Front disc / rear drum | SLA front; leaf-spring live axle rear | Muncie M21 4-spd |
| 1973–74 Trans Am 455 SD (auto) | ≈6.3–6.6 s | ≈14.3–14.7 s @ ~98–100 mph | ≈128–132 mph | ~3,750–3,900 lb | Front-engine, RWD | Front disc / rear drum | Performance springs/bars; HD shocks | TH400 3-spd auto |
| 1978 Trans Am W72 + WS6 (4-spd) | ≈7.2–7.6 s | ≈15.3–15.7 s @ ~90–92 mph | ≈122–125 mph | ~3,600–3,700 lb | Front-engine, RWD | Front disc / rear drum (J65 rear disc in 1979) | WS6 springs/bars; 15×8 wheels | Borg-Warner Super T-10 4-spd |
| 1979 Trans Am W72 + WS6 (4-spd) | ≈6.7–7.3 s | ≈15.0–15.4 s @ ~92–94 mph | ≈125–128 mph | ~3,650–3,750 lb | Front-engine, RWD | 4-wheel disc (WS6/J65) | WS6; quicker steering box | Borg-Warner Super T-10 4-spd |
| 1980 Trans Am Turbo 4.9 (Indy Pace Car) | ≈8.0–8.5 s | ≈16.2–16.8 s @ ~85–87 mph | ≈118–122 mph | ~3,650–3,800 lb | Front-engine, RWD | Front disc / rear drum or 4-wheel disc (WS6) | WS6 available; performance tires | TH350 3-spd auto |
| Mid-1970s Esprit (350/305, auto) | ≈9.5–11.0 s | ≈17.0–18.0 s | ≈110–115 mph | ~3,400–3,550 lb | Front-engine, RWD | Front disc / rear drum | Touring-oriented springs/bars | TH350 3-spd auto |
Variant Breakdown and Production Highlights
The Firebird family encompassed multiple trims and noteworthy limited runs. Production numbers below reflect widely published, model-specific figures.
| Variant/Trim | Years | Production (units) | Key Differences | Market/Region |
|---|---|---|---|---|
| Firebird Esprit | 1970–1981 | Varies by year (series production) | Luxury trim: upgraded interior, softer suspension; 350/305/301 V8s common | North America |
| Esprit "Sky Bird" (appearance) | 1977–1978 | Series production (no official consolidated total published) | Blue-on-blue theme, decals, trim-specific upholstery | North America |
| Esprit "Red Bird" (appearance) | 1978–1979 | Series production (no official consolidated total published) | Red exterior/interior theme, decals, accents | North America |
| Esprit "Yellow Bird" (appearance) | 1980 | Series production (no official consolidated total published) | Yellow theme with color-keyed wheels/trim | North America |
| Trans Am (base, various engines) | 1970–1981 | Varies by year (series production) | Aero bodywork, gauges, handling upgrades; engines per year | North America |
| Trans Am 400 Ram Air IV | 1970 | ≈88 | High-lift cam, round-port heads, forged rotating assembly | US/Canada |
| Trans Am 455 Super Duty | 1973 | 252 (Trans Am) | SD-455 with reinforced block, unique internals | US/Canada |
| Trans Am 455 Super Duty | 1974 | 943 (Trans Am) | Carryover SD-455, net-rated 290 hp | US/Canada |
| Trans Am 50th Anniversary LE (black/gold) | 1976 | Widely cited ≈2,590 | Black/gold livery, gold accents; many with Hurst hatches | US/Canada |
| Trans Am Special Edition (black/gold) | 1977–1978 | Series production; totals vary by Y82/Y84 package | Black/gold livery; Hurst or Fisher T-tops by year | US/Canada |
| Trans Am Y88 Gold Special Edition | 1978 | ≈8,666 | Solar gold paint, gold snowflakes, tan interiors | US/Canada |
| 10th Anniversary Trans Am | 1979 | 7,500 | Platinum/silver two-tone, special graphics, unique interior | US/Canada |
| Turbo Trans Am Indy Pace Car | 1980 | ≈5,700 | White/charcoal scheme, 4.9L Turbo, pace-car badging | US/Canada |
Ownership Notes: What Enthusiasts Should Know
- Maintenance: Pontiac V8s are durable with regular 3,000–5,000-mile oil changes. Expect timing set wear on many 1970s engines (OE nylon-tooth cam sprockets); upgrading to a steel set during rebuild is common.
- Cooling and fueling: Correct shroud, clutch fan, and radiator spec are crucial, especially on SD-455 and W72 cars. Quadrajet calibration (float height, secondary air-valve tension) must be right to avoid bog or lean surge.
- Transmissions: Muncie and Super T-10 4-speeds are stout; synchro wear shows as balky 2–3 shifts. TH350/TH400 autos respond to fresh accumulators and proper line pressure setup.
- Chassis and rust: Inspect rear window channels, cowl bases, lower fenders, trunk drop-offs, floor pans, and subframe mounts. T-top cars (Hurst, early; Fisher, later) demand close inspection for seal integrity and corrosion at the roof structure.
- Suspension: WS6 pieces transform the car—correct bushings, alignment (modest negative camber), and quality shocks yield period-excellent grip and steering accuracy. 1979 four-wheel discs (J65) add confidence and value.
- Parts availability: Excellent mechanical support exists. Trim unique to 1970–73 (Endura nose, early grilles) and special editions can be harder to source and pricier.
- Restoration difficulty: Straightforward for competent shops; originality matters on high-spec cars (RA IV, SD-455, special editions). Keep build sheets, PHS documentation, and drivetrain stampings organized.
- Service intervals: Ignition tune every 12k–15k miles (points-era), coolant every 2–3 years, diff and gearbox fluids at 30k–50k miles. Turbo 301 benefits from frequent oil service and careful warm-up/cool-down.
Cultural Relevance, Desirability, and the Market
Pop culture cemented the second-gen car’s image. The Trans Am’s black-and-gold Special Edition became a screen icon, while the Esprit earned its own television fame as Jim Rockford’s understated daily, underscoring the breadth of the Firebird brief. Auction activity consistently rewards authenticity and specification: documented 1970 Ram Air IV cars, numbers-matching SD-455s, 10th Anniversary cars with low mileage, and highly original Special Editions bring strong results, with top-tier examples known to command six-figure prices. Provenance and paperwork—build sheets, window stickers, and Pontiac Historic Services documentation—are decisive in valuations.
On the enthusiast scene, WS6-equipped late-1970s cars are prized for their handling and braking. SD-455s stand at the pinnacle for engineering significance, while clean Esprit special-appearance models have grown in appreciation as collectors rediscover period-correct colors and trims.
FAQs
Which second-gen Firebird/Trans Am is the fastest in stock form?
Well-tuned 1970 Ram Air IV and 1973–74 SD-455 Trans Ams post the strongest period acceleration, with W72/WS6 1979 four-speeds not far behind in real-world pace.
What’s the difference between W72 and WS6?
W72 is the higher-output 400-cubic-inch engine package (late 1970s). WS6 is a chassis package (suspension, wheels/tires, steering—plus four-wheel discs on many 1979 cars). They could be ordered together.
Is the 301 Turbo reliable?
When maintained and kept stock, it is serviceable. Key points are healthy cooling, correct ignition timing, intact vacuum/boost controls, and oil quality. Overboosting or detonation from poor fuel/tune shortens life.
Known problem areas?
Rust at rear window channels and subframe mounts, T-top leaks (especially early Hurst units), worn steering linkages, perished bushings, weak timing sets, and emissions-era vacuum spaghetti causing drivability issues if misrouted.
How does the Esprit differ from a Trans Am?
Esprit emphasizes comfort and appearance with softer suspension and smaller engines; Trans Am brings aero bodywork, gauges, firmer springs/bars, and the highest-output engines per year.
What documentation matters most for collectability?
Matching-numbers engine and transmission, correct carburetor and distributor codes, PHS paperwork, build sheet, original paint/trim codes, and correct special-edition option codes (e.g., Y82/Y84/Y88/J65/WS6).
What are typical auction values?
Authentic SD-455s and 1970 RA IV cars achieve the highest results; low-mileage, documented Special Editions and 10th Anniversary cars also command strong money. Condition, options, and documentation are the primary drivers.
Can four-wheel discs be retrofitted to non-WS6 cars?
Yes, factory-style J65 hardware can be installed with correct proportioning and parking-brake setup; originality-minded collectors prefer cars built that way.
Why This Generation Still Matters
The 1970–1981 Firebird family bridges two eras: the last of the high-compression bruisers and the dawn of systems-level chassis tuning. From Esprit elegance to Trans Am bravado, it proves that engineering finesse could carry a performance coupe through the 1970s with credibility intact—and leave a rich field for collectors and drivers alike.
