Buick had been the first GM division to bring a personal luxury car to market with its full-size 1963 Riviera but was otherwise slow to react to the developing lower-priced mid-size personal luxury market, which Pontiac created with the 1969 Grand Prix and Chevrolet with the Monte Carlo the following year, 1970.
At the same time Oldsmobile added a formal notchback coupe to its intermediate line, the Cutlass Supreme, in 1970 and that model soon became Olds' best selling intermediate. Wanting a model that could be marketed to compete against the Olds Cutlass Supreme as well as the Grand Prix and Monte Carlo, Buick introduced the Regal for 1973, as a top line special coupe in that division's intermediate A-body line, the Century.
The year 1973 also marked the introduction of the first major restyling of GM's intermediate A-body design since 1968. A highly-trimmed, notchback coupe, the first Regal shared its front and rear styling with its Century parent with distinctions amounting to differing grilles and taillight lenses.
The Regal shared the same "Colonnade" pillared hardtop roofline (a hardtop with center pillar but frameless doors unlike a sedan body) and greenhouse (window area) with the Grand Prix, Monte Carlo and Cutlass Supreme as well as the lower-priced Buick Century Luxus coupe.
Like its corporate cousins, the Regal (and Luxus) featured the newly fashionable opera windows, which were small fixed rear-side windows surrounded by sheetmetal, instead of the traditional roll-down windows. Only the Colonnade hardtop coupe was offered in the Regal line in 1973, but a new four-door Colonnade sedan (with six-window-greenhouse and frameless door windows) debuted in 1974 and continued through the 1977 model year.
Although in terms of overall dimensions the car was smaller, interior head and legroom dimensions were comparable to, or even better than, the earlier Buick models. The Regal Coupe, as with many American cars, could be tailored almost exactly to customer requirements by the option of 2 different engines, 2 transmissions, and a host of other, smaller, items.
These ranged from an outside rear-view-mirror-mounted temperature gauge to a limited-slip differeritial. The standard engine for the Regal was a 5736 cc V8 which produced a modest 140 bhp breathing through a 2-barrel (choke) Rochester carburetor. The top speed ranged from 98 mph to 104 mph depending on the engine.
For 1977, the last year of the Generation 1 Regal, the car featured new emission control systems on the engine in addition to the catalytic converter used in previous years. This was to enable the car to meet the more stringent regulations which had been introduced since the car first appeared. The basis of the improved control was an exhaust gas recirculation system, used in conjunction with various carburation and timing settings depending on the State in which the cars were sold.
Vehicles sold for use in counties that were entirely above 4000 ft, outside of California, had to be certified for use under those atmospheric conditions. Some of the extras available were a sun-roof, tinted glass, a 'firm ride and handling package', electric door locks and various 'in-car entertainment' options. A slightly larger, 4-door Sedan, the Buick Regal Colonnade Sedan, supplements the coupe but was of basically the same mechanical specification.
The model lasted five years with minimal changes, although there was a fairly substantial facelift in 1976 (for the coupe only - sedans stayed with original 1973 sheetmetal through 1977), which incorporated the recently legalized square headlights (horizontally-mounted on coupes, and vertically on sedans - much like the mid-1960s Pontiacs).
The Regal was most commonly powered by Buick's 350 in³ V8, which was standard equipment on all models in 1973 and 1974 and optional on coupes but remained standard on sedans from 1975 to 1977, and the larger 455 in³ V8 was optional in 1973 and 1974 only. Starting in 1975, Regal coupes came standard with Buick's resurrected 231 cu in (3.8 L) V6 engine previously offered on the Skylark from 1964 to 1967; the engine's tooling had been sold to Kaiser Motors for use in Jeep models (Kaiser was purchased by American Motors in 1970 and Jeep became an AMC division) and sold back to GM by AMC in 1974. In 1975 and 1976, the Century and Regal were the only mid-sized cars in America to offer V6 engines. The bolt pattern for this vehicle is 5x120.7.The Century designation was quietly dropped from the Regal in 1975.
- Engine: Front-mounted, water cooled V8. 96.5 mm (3.80 in) bore x 97.8 mm (3.85 in) stroke 5736 cc. Cast-iron cylinder block and heads. Compression ratio (all models) 8.0:1, 5 main bearings; 2 valves per cylinder operated, via rockers, by a single camshaft at the centre of the V. 1 Rochester downdraught 2-GV carburetor (350-2) or 1 Rochester downdraught 4- MV carburetor (350-4).
- Power: Maximum power: (SAE) 140 bhp at 3200 rpm (350-2) 155 bhp at 3400 rpm (350-4); maximum torque (SAE) 280 Ib ft at 1400 rpm (350-2) or 2751b ft at 1800 rpm (350-4).
- Transmission: Turbo Hydramatic 350 automatic. Ratios: 1st 2.52:1, 2nd 1.52, 3rd 1, reverse 1.93:1; hypoid-bevel final drive. Ratio: 2.73 (standard) or 3.08 (performance option).
- Suspension: Front: independent with lower trailing links, coil springs, an anti-roll bar and telescopic dampers. Rear: Non-independent with a rigid rear axle, lower trailing radius arms, upper oblique torque arms, coil spring and telescopic dampers.
- Steering: Recirculating ball with variable ratio power assistance. Turns from lock to lock: 6.64 (quick ratio available).
- Brakes: Discs front and drums
rear. Total swept area 334.2 sq
in (2144 sq cm). Servo assistance optional extra.
- Wheels: 14 in x 6 in steel.
- Tires: G78 x 14 in steel bolted radials.
- Dimensions and Weight: Wheelbase 116 in (sedan) 112 in (coupe); track front 61.5 in, rear 60.7 in (both models); length 213.5 in (sedan) 209.7 in (coupe); width 79.0 in (sedan 77.0 in (coupe); height 53.6 in (sedan) 52.6 in (coupe); kerb weight 40521b approx. (sedan), 37071b (coupe).
- Body/Chassis: Saloon, 4-door, 4 seats, or Coupe 2-door, 4 seats. Perimeter box type.
- Performance: Top speed 98 mph (350-2), 104 mph (350-4). Fuel consumption 20 mpg (350-2), 16 mpg (350-4).
- Interior: Regal interiors were generally more luxurious than lesser Century models with woodgrain trim on dashboard and door panels, along with door-pull straps and notchback bench seats with center armrests with either cloth, velour or vinyl upholstery. Optionally available throughout the run was a 60/40 split bench seat with armrest. For 1976 and 1977, the Regal coupe was available with the S/R option that included reclining bucket seats with corduroy upholstery.