View Single Post
  #3  
Old 11-29-2012, 01:02 PM
Man of Steel's Avatar
Man of Steel Man of Steel is offline
Enthusiast
 
Join Date: Sep 2006
Posts: 1,646
The Netherlands
Chevrolet Chevelle (3rd gen) 1973-1977

The most extensive redesign in its 10-year history marked the 1973 Chevelle, and with it marked the end of hardtops as we knew them. The newly-named "Colonnade Hardtop" featured a semi-fastback roofline, frameless door glass and fixed, styled "B" pillars, structurally strong enough to contribute to occupant safety of a roll-over type accident. GM had anticipated Federal roll-over safety standards that ironically didn't materialize. Distinctive rear quarter glass on 2-door coupes and new side windows with styled center pillars were featured on 4-door models. Rear windows on coupes no longer opened. In addition to the new roofline, front and rear ends looked markedly different this year as 1973 was the year of the federally-mandated 5 mph (8.0 km/h) front bumper, adding to the car's length. Additional new body features were an acoustical double-panel roof, tighter-fitting glass and flush style outside door handles. Wheelbase dimensions were retained; a sporty 112 inches (2,800 mm) for coupes and 116 inches (2,900 mm) for sedans and station wagons, but bodies were five inches (127 mm) longer and an inch wider with a 1-inch (25 mm) wider wheel track. The station wagon, available in 6 or 9 passenger seating, featured a new counterbalanced liftgate which allowed for easier entry and loading up to 85 cubic feet.

1973 models also introduced molded full foam front and rear seat construction, a flow-through power ventilation system, an inside hood release, refined Delcotron generator and sealed side-terminal battery, a larger 22 gallon fuel tank, and "flush and dry" rocker panels introduced first on the redesigned 1971 full-size Chevrolets. Another structural improvement was a stronger design for the side door guard beams. New options included swivel bucket seats (with console) for coupes and Turbine I urethane (backed by steel) wheels, as was the instrument gauge cluster. A power moonroof was an option 1973-75. Interior roominess of the '73 Chevelle was improved, particularly in the rear. Headroom was up slightly and shoulder room gains were by 1.6 inches (41 mm). Rear seat legroom was up 3.5 inches (89 mm) in sedans. Another was a 15.3-cubic-foot (430 L) luggage capacity, an increase of 2.5 cubic feet (71 L) over 1972 models. Still another benefit of the new body designs was greatly improved visibility, up 25% in coupes and wagons, and 35% in sedans. The unusually thin windshield pillars also contributed to much better visibility.

The chassis design was as new as the bodies - with an all-new, sturdier perimeter frame, new chassis/body mounts, larger 8 inch rear axle, wider 6-inch wheel rim width, refined rear control arm bushings, increased front and rear suspension travel, new shock absorber location, and improved front suspension geometry - The left wheel was adjusted to have slightly more positive camber than the right which resulted in a more uniform and stable steering feel on high-crown road surfaces while maintaining excellent freeway cruise stability. Clearances for spring travel were also improved for a smoother ride over all types of surfaces; the coil springs at each wheel were computer-selected to match the individual car's weight. Front disc brakes were now standard on all '73 Chevelles. John Z. DeLorean, Chevrolet's dynamic general manager during the design phase of the new Chevelles, left just as they were being announced. He departed in late September 1972 to start a brief stint as vice president of General Motors's Car and Truck Group. DeLorean left the new Chevelle an important legacy, though. He and Alex Mair, then Chevrolet's chief engineer, championed great handling. Like many new Chevrolet models of the era, the new Chevelles would be exceptional drivers' cars. Five power teams were available for 1973 Chevelle models; the 250 inline-six and 307 2-barrel V8 both rated at 110 hp (82 kW) were std. engines on Deluxe and Malibu. The 350 2-barrel V8 of 145 hp (108 kW) was the base Laguna engine. Options for any Chevelle included a 350 4-barrel V8 of 175 hp (130 kW) and a 454 4-barrel V8 rated at 245 hp (183 kW). Hardened engine valve seats and hydraulic camshafts made these engines reliable for many miles, and allowed them to accept the increasingly popular unleaded regular gasoline. 3 speed manual transmission was standard; 4 speed manual and Turbo Hydra-Matic 3 speed automatic were optional. Crossflow radiators and coolant reservoirs that prevented air from entering the system prevented overheating.

Malibu and the newly named Deluxe series base model featured the new 5 mph (8.0 km/h) bumper system with a large chrome front bumper and a chrome rear bumper. Malibu series interiors included cloth and vinyl or all vinyl seat trim and deep-twist carpeting. Deluxe series interiors featured cloth and vinyl or knit vinyl seat trim. Floor coverings were color-keyed in vinyl-coated rubber. The SS was now a trim option limited to the mid-level Malibu series. Shoppers could even get an SS station wagon this year - with the option of a 454-cubic-inch V8 engine, no less—but the mix of sport and utilitarian wagon virtues would last only a single season. Included was a black grill with SS emblem, lower bodyside and wheel opening striping, bright roof drip moldings, color-keyed dual sport mirrors, black taillight bezels, SS fender and rear panel emblems, special front and rear stabilizer bars, 14x7 inch rally wheels, 70-series raised white lettered tires, special instrumentation and SS interior emblems. The SS option required an available 350 or 454 V8 with 4-speed or Turbo Hydra-Matic transmission.

Chevrolet honored California beach resorts once again by naming the top Chevelle series Laguna with the Malibu taking the middle spot while the base series was called simply Deluxe. In addition to the standard 350 2 barrel V8, Laguna models featured specific front and rear styling including a body-colored urethane front end concealing the new 5 mph bumper system. On minor impact the urethane nose cone, backed up by shock- absorbing cylinders, deflects and rebounds; Laguna models also featured a specific diecast chrome grille with bowtie emblem, a body-colored (steel) rear bumper, front and rear bumper rub strips, bright roof drip moldings, bright wheel opening moldings, chrome taillight bezels, full wheel covers, and Laguna fender nameplates. Two Laguna station wagons were introduced, including a Laguna Estate. Laguna interiors were pattern cloth and vinyl or optional breathable all-vinyl upholstery, distinctive door trim with map pockets, deep-twist carpeting, woodgrain vinyl accents, and Laguna nameplates. Consumers continued to snap up Chevelles: 327,631 of them in the 1973 model year, plus 59,108 station wagons. The Malibu versions of the Chevelle continued to sell best by a wide margin, but the costlier Laguna coupe and sedan made a respectable showing, with 56,036 going to customers. Super Sport options went on 28,647 Chevelles of which 2500 held the big 454-cubic-inch engine. The SS option was dropped at the end of the model year.

Yearly design changes to the front and rear mark the aesthetic differences as in previous years. The Chevelles were top sellers for GM as was the Oldsmobile Cutlass, which used the same corporate A-body platform.

1974 Chevelles featured new grilles, new taillights and 5 mph (8.0 km/h) rear bumpers (in addition to the 5 mph (8.0 km/h) front bumper added in '73) The Laguna name had debuted on the 1973 Chevelle as the top-line series in all body-styles, but the 1974 Laguna Type S-3 came only as a coupe, which combined Laguna luxury with the superior road manners of the SS which it replaced. Handling was further enhanced with the addition of new GR70-15 radial-ply tires. The new Laguna S-3 sported the urethane front end with a revised grill and new parking lamps, augmented at the rear by new taillights. A federally-mandated 5 mph (8.0 km/h) chrome rear bumper replaced the body-colored steel 2.5 mph (4.0 km/h) version from '73. Standard equipment included a console, a vinyl roof, opera-type vertical rear quarter windows which could be covered with horizontal ribs for a few dollars extra; body side striping, Laguna S3 badging, rally wheels, 4 spoke steering wheel as well as firmer shocks/springs, a front stabilizer bar, and fat HR70x15 tires on Rally wheels. Front occupants rode in swivel bucket seats, and the driver faced a six-dial instrument cluster. Production totaled 15,792 cars, with prices starting at $3,723 - but with plenty of options to send the bottom line past $5,000. Engine offerings included a standard 145 horsepower (108 kW) 350 two-barrel V8, with optional powerplants including a 150 horsepower (110 kW) 400 two-barrel V8, 180 horsepower (130 kW) 400 four-barrel V8 and 230 horsepower (170 kW) 454 four-barrel V8, except in California where a 155 horsepower (116 kW) 350 four-barrel V8 was standard and the 400 and 454 engines were optional. The 454 was available with the Turbo Hydra-Matic automatic 400 or Muncie 4 speed manual transmissions. 3-point seat belts with integrated shoulder belts were introduced as on all Chevrolet models.

Last edited by Man of Steel; 11-30-2012 at 04:39 AM.
Reply With Quote