1975 Chevrolet Corvette Stingray SPOTLIGHT
Arkus-Duntov had worked for General Motors for over two decades, and during that time, had been one of the great champions of performance within GM and specifically Chevrolet. The Corvette connection was particularly relevant, as Arkus-Duntov had approached GM about a job after seeing the prototype Corvette sports roadster doing the rounds of the GM Motorama in the early 1950s, before its production debut. After rising to the position of Director of High Performance Vehicle Design and Development for GM's Chevrolet division in 1956, Arkus-Duntov's influence on the Corvette's development was finally acknowledged when he was named as the Corvette's Chief Engineer in 1968.
What Arkus-Duntov thought of the Corvette that appeared in the year of his departure from General Motors is not recorded, but there's little doubt he wouldn't have been impressed. However, the reality was that the "horsepower wars" were well and truly over by the mid-1970s. The mighty 330hp LT-1, 365hp LS5 454 V8 and 425hp LS6 454 V8 became victims of sky-high insurance premiums for high performance cars, as well as an increasing raft of federally-mandated regulations regarding vehicle safety and engine emissions. This was exacerbated by the first "energy crisis" of 1973/74, which effectively put the final nail in the coffin of thirsty, high-performance V8 engines.
The result was that the 1975 Corvette Stingray was offered with only one engine, in two stages of tune. Compare this to 1969 when seven different options - from 300 to 430 horses - were available. Both the '75 options were based on the 350ci small block V8. In standard spec, this produced 165hp. Optioning up to the 'L82' offered 205hp, with both variants having a catalytic converter fitted as standard to reduce exhaust emissions. Mated to the V8 for the first time in '75 was a new 'High Energy' ignition, which produced a hotter, more reliable spark, and thus more complete combustion to further reduce emissions. Reflecting the move away from high performance during this period was the fact that less than 10 percent of buyers chose the 205hp option. The standard transmission was a four speed manual, with GM's Turbo Hydra-matic auto trans available as a no-cost option, as well as closer and wider ratio manuals.
All the doom and gloom around nosediving horsepower ratings didn't seem to affect buyers. Quite the opposite, in fact. Corvette production steadily rose through the 1970s, with 38,465 of the '75 models produced. This figure continued to climb after 1975 and actually topped 50,000 before the end of the decade. Impressive sales for the 'Vette through this period showed that buyers weren't just after performance any more. They wanted comforts, luxuries and appearance features. The growth in the "personal luxury" segment through the 1970s reflected this, and the Corvette was one of many models to react with a range of both optional and standard comfort features.
While vinyl upholstery was still standard in 1975, buyers could chose one of three different shades of leather trim for the bucket seats, with other options including 'custom interior trim' (combining leather seats with fake wood grain door & console trim and carpeted lower door sections), rear window demister, power steering, electric windows and air conditioning. The adoption rate for the latter option had been growing year on year to the point that more than 80 percent of Corvettes were being fitted with it. The increasing effectiveness of air conditioning units was one of the main factors behind the lessening demand for convertibles, but the 't-top' removable roof panels introduced with the Corvette coupes in 1968 played a part as well.
At the start of the 1970s, close to 40 percent of Corvettes produced were softtops. By 1974, that figure had dropped to only 16 percent. With most other GM divisions having either already dropped or planning to drop their convertible models in 1975 (due to fears that convertibles would be mandated out of existence by further safety regulations), Corvette followed suit, with the last softops offered that year. One would have thought that the "final year" for the Corvette convertible would have caused a run on sales, like it did with the Cadillac a year later, but not so. 1975 convertible production accounted for only 12 percent of the total, a further drop from 1974.
Externally, the 1975 Corvette Stingray differed little from the previous year's model. The 5mph (8kph) impact bumpers front and rear had become standard in 1974, but the '75 featured a one-piece design for the rear bumper, and the construction underneath those 'endura' urethane end caps was modified to improve impact absorption. Additionally, both front and rear bumpers featured small rubber-tipped extensions. External badging was almost identical to the '74 model, and ten different exterior colours were offered, as per 1974. Turbine-style wheels were standard, with white-letter Firestone tyres selected by almost 80-percent of '75 Corvette buyers.
Other popular options in 1975 included power brakes (93 percent takeup rate), power windows (74 percent), power steering (97 percent), adjustable steering column (82 percent) and automatic transmission (74 percent). Least popular were two different suspension options. One, curiously referred to as the 'Off Road Suspension and Brake Package', was fitted to fewer than 150 Corvettes (less than 1 percent of production), with the other 'gymkhana suspension' package only finding favour with 8 percent of buyers.
Today, the '75 Corvette in strictly stock specification is reasonably rare, but much moreso in convertible form. The "last year" status of the '75 (at least until the softop's return on the 1986 model) doesn't appear to have made it markedly more collectable, but in general, '75 and older Corvette ragtops tend to attract higher prices than the coupes. Corvette Stingrays from the C3 era, like this one, remain popular and are well supported by Australian clubs and aftermarket specialists, so repairs and spares shouldn't be a problem. The other plus with the '75, and indeed any Corvette, is the fibreglass body that is more easily repaired than steel bodies and panels.
In initial comparison, the 350-engined '75 suffers against the significantly more powerful earlier models. However, the fact remains that not every 'Vette buyer wants tyre-shredding grunt, and a lot of the power from a 454, for example, is either unusable or potentially licence-losing. Of course, if that's what you want, you can always replace the stock running gear with the powertrain and transmission of your choice. A stock 1975 'Vette is still pretty quick, with enough oomph for most situations, as well as good handling and braking. For some, however, the power and usability is irrelevant, they just love that evergreen C3 Stingray look.
SPECIFICATIONS: 1975 Chevrolet Corvette Stingray
Engine: 350 cubic inch OHV V8
Bore/Stroke: 4.00-inch x 3.48-inch
Compression: 8.5:1
Power/torque: 165bhp @ 3800rpm / 255 lb/ft @ 2400rpm
Fuel system: Rochester 'Quadrajet' 4 barrel carburettor
Ignition: Distributor
Cooling system: Liquid
Electrics: 12 Volt
Transmision: 4-speed close ratio manual
Front Suspension: Independent unequal-length A-arms with coilover shocks and stabiliser bars
Rear Suspension: Transverse semi-elliptic leaf spring w/shock absorbers and anti-roll bar
Steering: Recirculating ball w/optional power assist
Front brakes: 11.75-inch ventilated disc
Rear brakes: 11.75-inch ventilated disc
Wheels: 15 x 8-inch Fr/Rr
Wheelbase: 98 in (2489mm)
Length: 185.5 in (4712mm)
Width: 69 in (1752mm)
Height: 47.4 in (1204mm)
Weight: 3,532 lb (1602kg)
0-100 kph: 8.5 seconds - approx
Top Speed: 200 kph approx
TRIVIA
Brochures for the '75 Corvette reflected the more sober times the car was introduced into. Previous taglines pitching the "the true sports car" at "performance and style-minded individuals" was replaced with the much less sexy "makes excitement make sense", in an effort to depict the Corvette as a sort-of common sense sportscar.
In the early 1970s, Chevrolet had been toying with the idea of a mid-engined Corvette, and even one with a rotary engine. The first oil crisis of 1973-74 effectively killed the traditionally thirsty rotary, while the increasing sales of the 'Vette through the mid-'70s made a platform switch unnecessary, so both these ideas remained concepts only.
For the first time in close to two decades, the 1975 Corvette had a competitor on the "home grown" sportscar stakes, in the form of the Bricklin 'SV1' created by Malclm Bricklin. Dubbed the "safety sports car", the Bricklin had overall dimensions and profile similar to the Corvette, and was also a two seater, but featured an opening hatchback-style rear, and distinctive energy-absorbing front and rear bumpers. Poor build quality and supply problems concerning engines and transmissions saw SV1 production cease in the same year.
