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JP created the topic: 1963 Sting Ray Corvette: history and pix
1963: Great Corvette Years
In the May 1963 issue of Motor Trend magazine, staffer Jim Wright reported: "For the first time in its 10-year history the Corvette ... is in such demand that the factory has had to put on a second shift and still can't begin to supply cars fast enough." He went on to state that customers were having to wait 60 days for dealers to fill orders and that no one would discount or even offer much of a trade-in allowance.
1963 corvette sting ray side
What was the object of all this interest? It was the incredible 1963 Corvette Sting Ray. As the first completely new edition of America's sports car since the original, it was both a revolution and a revelation. In addition to the traditional roadster, Chevrolet fielded a beautiful new grand touring fastback coupe. Both not only looked sensational but had the speed and agility to match. To say the Sting Ray was an instant hit is an understatement: for the model year, Corvette production soared to 21,513 units, a striking 50 percent gain over the record-setting 1962 total. As the first of an entirely new line, the '63, especially the coupe, has since become the most coveted single Corvette model apart from the 1953 original. For 'Vette fans and many partisan critics, it remains a landmark in American automotive design.
1963 corvette sting ray
The Sting Ray hit the market with a flying start and a look that seemed straight out of the future, but its basics had already been in place for several years. In fact, its origins probably go back as far as 1958, when William L. Mitchell took over as head of the GM Styling Staff on Harley Earl's retirement.
Like his predecessor, Mitchell considered the Corvette "his" personal, pet project. The 1960 model was his first challenge, and he got Bob McLean to assist him. McLean, remember, had been largely responsible for the original 1953 Motorama Corvette. Here he devised a fastback coupe with peaked fenders, a long nose, and a short, cropped tail. While the look met with general approval at GM, the chassis and drivetrains Zora Arkus-Duntov proposed for the new envelope were considered too expensive for the Corvette's intended market. A completely new design was put on the back burner, and the production 1960 Corvette emerged as simply a refined carryover of the 1958-59 package. But McLean's earlier design work was not forgotten.
Much of the eventual production Sting Ray design came directly from Mitchell and it was one of the "bootleg" projects he carried on without GM's formal approval. The experimental Corvette SS that had made the assault on Sebring in 1957 had taught Duntov much about chassis design, and Mitchell had bought the "mule" development car from that effort. He wasn't about to let this car die, and he spirited the chassis away to his "Studio X" special projects area. There he designed a brand-new body, put it on the mule chassis, and took it racing, ostensibly as a private entry.
1963 Chevrolet Corvette Sting Ray Rear Side View
Thus was born the "Sting Ray Special," as it was initially titled, financed by Mitchell with a little help from his friends. Though it never placed first, Dr. Dick Thompson, the "flying dentist," made a strong showing against many better-backed European competitors, placing high enough in the standings to win the SCCA's national C-Modified championship in 1959 and again in 1960. But it wasn't so much the Stingray's track performance as its beauty that earned widespread attention. It never ran as a "Corvette" or under the GM flag, of course. But it looked suspiciously like a GM product-almost too complete for a racer. Some observers began wondering whether it wasn't really a sneak peek at the next Corvette. The basic shape made a favorable impression on the public enough to provide strong impetus for the shape of the next generation production model. Thus, the eventual 1963 styling was rendered more or less a fait accompli many months before the formal design program was started. By working outside the GM system, Mitchell accomplished what he probably could not have achieved by working within it.
The 1963 Sting Ray models featured redesigned interiors and suspensions.
Meanwhile, planning for future Corvettes was proceeding, and at least four different approaches were pursued during 1958-60. One was the so-called Q-Corvette, begun in 1957 as a spinoff from the radical rear engine Q-series sedans proposed for 1960. This program envisioned a smaller Corvette with independent rear suspension plus coupe bodywork with lines not unlike those of Mitchell's racer. The effort got as far as a steel-body prototype before the sedans were shelved. This rendered a separate Corvette much too costly in view of projected sales, so it, too, was shelved. A second effort involved use of some Q-model componentry for a rear-engine 'Vette based on the powertrain of the Corvair compact. This progressed to a full-scale clay with taut, two-seat open bodywork featuring crisply creased body sides leading into a beveled nose and tail. Two engines were proposed, the Corvair flat-six and the 'Vette's usual V-8. Duntov liked the idea, but costs again proved prohibitive.
A third idea was a major reskinning for the third-generation 1958-59 platform. Interestingly, this proposal, a possible 1962 development, featured Mitchell's Stingray-inspired "ducktail" rear end in virtually the same form as it actually appeared for 1961. The front end was something else: a low-set rectangular opening surmounted by bulging front fenders and flanked by quad headlights recessed under curious jutting "eyelids." All things considered, it's probably just as well this one didn't make it.
What did make it was the fourth effort, begun at Styling near the end of 1959. Given the experimental project number XP-720, it would lead directly to the production 1963 Sting Ray. According to Duntov, the overriding goals for this project were ''better driver and passenger accommodations, better luggage space, better ride, better handling and higher performance." As was usually the case with Duntov's projects, the "higher performance" part had higher priority.
The 1963 Sting Ray Interior
The chassis was entirely revamped and-shades of 1952-the passenger compartment was placed as far back as possible. The center of gravity was lowered since this would not only improve handling but, as Duntov felt, would also enhance ride quality. Ground clearance ended up at just five inches, though the passengers now rode within the frame rather than on top of it, and the center of gravity was 16.5 inches from the road, 2.5 inches less than on previous Corvettes. The 102-inch wheelbase also shrunk, down to 98 inches. With major driveline components placed as low and close to the center as possible, the XP720 emerged slightly tail heavy, the rear wheels carrying 53 percent of the total static curb weight.
1963 Chevrolet Corvette Sting Ray Coupe Cutaway.
The old X-braced frame went by the boards in favor of a ladder-type design with five cross members. This was chosen to ensure better torsional rigidity, an important consideration because of the minimum 300 bhp initially envisioned for the XP720. The independent suspension that Duntov insisted on would increase lateral stress on the frame in hard cornering, thus requiring the extra torsional strength. At one point, though, frame stiffness was found to be more than the engineers needed. While it might help road holding, it would exact a penalty in ride harshness. A compromise was struck for production, providing more than adequate frame stiffness plus the desired ride characteristics. It was also less costly to build, no doubt an overriding concern given the expense involved in switching to an independent rear suspension.
In fact, cost was the reason GM management used in attempting to talk Duntov out of it altogether. But Duntov would have it no other way, and to justify its expense he said it would help Chevrolet move 30,000 Corvettes a year.
While Duntov was earnestly seeking an innovative and ultimately producible new chassis, the stylists had only to clean up and refine the basic Stingray shape that had been around for some three years. The earliest XP-7 20 mockups looked like nothing more than the racer with a fastback roof. Wind tunnel testing helped to refine the shape, as did more practical matters like interior space, windshield curvatures, and tooling limitations.
Both body styles were tested extensively in production-ready form at the Cal Tech wind tunnel, and body engineers spent a great deal of effort on the inner structure. Compared to the '62 Corvette, the Sting Ray had nearly twice as much steel support built into its central body structure, which resembled a racing-style ''birdcage" frame. The extra steel was balanced by a reduction in fiberglass content, so that the finished product actually weighed a bit less than the '62 roadster. Despite the tighter wheelbase, interior room was as good as before and, thanks to the reinforcing steel "girder," the cockpit was stronger and safer.
1963 Chevrolet Corvette Sting Ray split window.
The Sting Ray was far more than just a beautiful body. True, engines, transmissions and axle ratios were carryovers from 1962, and from the doorjambs back, the convertible version was quite similar in appearance to the 1961-62 models. But in nearly every other respect this was a totally new Corvette. The most dramatic evidence of that was the first production Corvette coupe. This futuristic fastback attracted even larger crowds than the roadster, partly because of one distinctive styling feature: a split rear window.
McLean's original design called for a one-piece backlight, and it was Mitchell who came up with the "backbone." The split-window configuration was not a unanimous decision. Duntov, for one, was opposed because it cluttered up the view to the rear. But purely practical arguments would not suffice for Mitchell, who insisted, "If you take that off, you might as well forget the whole thing." His goal was a flowing "spine" from front to rear, beginning as a rise in the center of the hood (necessary to clear the plenum chamber on engines with fuel injection) and continuing as a crease line over the roof, through the window and down the deck. Mitchell was the boss, so he got his way, and most Corvette fans today would vote with him on aesthetics. The split-window Sting Ray coupe remains one of the most stunning automobiles of all time. It certainly met one of Mitchell's prime criteria: it wouldn't be mistaken for anything else.
But the split backlight took a beating in the press. Road & Track disliked "that silly bar," and Car and Driver agreed, saying the "central window partition ruins our rear view." Sometimes it is difficult for the motoring press to see the styling forest for the tress, but many customers did. They loved this Corvette because it was a true go-fast machine that looked supersonic even just parked. Ultimately, Mitchell relented. He had his year of production, thus creating a car for future collectors. However, many split window coupes were lost to customizers, some of whom fitted one-piece Plexiglas windows as a substitute. Shortly after this became status quo for the '64 model, a one-piece glass backlight window became available as a replacement item through Chevy dealers. Undoubtedly, many more '63 Corvettes lost their value as collectibles-and their distinctive "split" personality.
1963 Chevrolet Corvette Sting Ray Convertible hide-away front lights.
The remainder of Mitchell's design was equally stunning. Quad headlamps were retained, but now they were hidden, mounted in pivoting sections that fit flush with and matched the front-end contours. This was the first car with hidden lights since the 1942 DeSoto. Another DeSoto-type element, this time from 1955-56, was the "gullwing'' dash styling. “The dual cockpit was widely criticized at the time," one Corvette designer remembers, "but it was a very fresh approach to two-passenger styling."
1963 Chevrolet Corvette Sting Ray Convertible door detail, etc.
Other interesting design elements included an attractive dip in the beltline at the trailing upper edge of the door, and the coupe's doors were cut into the roof, a feature now de rigeur at Ford. The interior received a few updates, such as cowl-top ventilation and an improved heater. Luggage space was also improved, though the Sting Ray was criticized for lack of an external trunk lid (the only access was through the passenger compartment). The spare tire was carried in a sealed fiberglass housing at the rear, hinged to drop to the ground when released. Styling critics chided the use of dummy vents in the hood and on the coupe's B-pillars. At one time these were intended to be functional, but the old cost gremlin again reared its ugly head. It didn't matter much anyway, for these wouldn't last.
Besides the roadster and the new coupe, Chevrolet also toyed with a four-place version of the Sting Ray design. The idea was suggested by Ed Cole, who felt that a back-seat model would give the Corvette broader market coverage, enabling it to compete directly with a number of upscale European 2+2s while appealing to those 'Vette fans that occasionally needed to carry more than one passenger. The plan got as far as a full-size mockup, photographed in the Design Staff auditorium in 1962 alongside a contemporary Ford Thunderbird, which was seen as its main domestic rival.
Based on the production approved split-window coupe, the proposed four-seater had some 10 extra inches grafted in between the wheel centers, plus a higher roofline (to provide a semblance of rear seat headroom), revised rear fender contours, and a pair of fully engineered back seats with fold-down backrests. Unhappily, the resulting proportions were rather ungainly, which no doubt convinced some executives that the 2+2 might dilute the styling impact of the two-seat models. Chevy abandoned the idea, though it was basically a good one. As a matter of fact, Jaguar thought of the same thing, and a few years later released a stretched-wheelbase version of its slinky two-seat E-Type coupe with similarly awkward lines.
Though not as obvious as the styling, the new chassis was just as important to the Sting Ray's success. The solid rear axle of old was exchanged for the first independent rear suspension in 'Vette history. This consisted of a frame-mounted differential joined to each wheel by half shafts, with U-joints at either end. The entire assembly was considerably lighter than the old solid axle and brought about a significant reduction in unsprung weight. The differential was mounted in rubber cushioned struts, which helped reduce ride harshness while improving tire adhesion, especially over rougher roads. A single transverse leaf spring was bolted to the rear of the differential case. Attached to either side of the case was a control arm (trailing arm) extending laterally to the hub carriers and slightly forward. A pair of trailing radius rods was fitted behind. Twin coil springs had been considered at one point, but they took up too much space in this smaller car. The half shafts acted like upper control arms in this design, with the lower arms controlling vertical wheel motion. The trailing rods took care of fore and aft wheel motion while transferring braking torque to the frame. The shock absorbers were the conventional twin-tube type.
The new five-cross member frame weighed about the same as the old X-brace chassis. With a curb weight of 3,030 pounds, though, the base convertible came out about 100 pounds heavier than its 1962 counterpart. The frame rails were wider and boxed for stiffness, helping to provide 50 percent more torsional rigidity, meaning less twisting motion during cornering, especially over bumps.
Front suspension geometry was much as before, with unequal-length upper and lower arms and coil springs concentric with the tubular shocks. An anti-roll bar was standard. Steering was conventional recirculating-ball with an overall ratio of 19.6:1. However, this could be easily changed to a much quicker 17.1:1 by disconnecting the tie rods and moving them to secondary mounting holes in the steering arm. Bolted to the frame rail at one end and to the relay rod at the other was a steering damper (essentially a shock absorber), which helped soak up bumps before they reached the steering wheel. Power assist was optional and came with the faster ratio.
1963 Chevrolet Corvette Pilot Line Sting Ray.
Maneuverability of the '63 Corvette was improved by the shorter wheelbase. Although this would ordinarily imply a choppier ride, the altered weight distribution partly compensated. Less weight on the front wheels also meant easier steering, and power steering wasn't often ordered. The additional 80 pounds over the rear wheels also improved traction and gave the Sting Ray a noticeable rear-end squat during hard acceleration.
Stopping power also improved. The four-wheel drum brakes had 11-inch-diameter drums, the same as before, but the linings were wider. Sintered-metallic linings, segmented for cooling, were again optional. Optional finned drums were made from aluminum rather than cast iron to improve cooling and reduce unsprung weight. With that combination, brake fade from excessive heat was reduced considerably. Power assist was available with both standard and high-performance brake packages. Availability of power assist for both brakes and steering was a first for Corvette. Also new was an alternator instead of a generator. Other such evolutionary changes included positive crankcase ventilation, a smaller flywheel, and an aluminum clutch housing.
1963 Chevrolet Corvette Pilot Line Sting Ray 327 engine.
Sting Ray drivelines, as noted, were largely a carryover from '62. There was a choice of four engines, three transmissions and six axle ratios. The 327 V-8 was offered in carbureted form with 250, 300 or 340 bhp. The base and step-up versions used hydraulic lifters, a mild cam, a forged-steel crankshaft, 10.5:1 compression, a single-point distributor, and dual exhausts. The 300 produced its extra power with a larger four-barrel carburetor (Carter AFB instead of the 250's Carter WCFB), larger intake valves and a bigger exhaust manifold. By opting for fuel injection, the buyer paid $430.40 to get 360 ponies under the hood. As base prices were $4,252 for the coupe and $4,037 for the convertible, injection was looking quite pricey. A three-speed manual transmission was again standard, but neither that nor the optional Powerglide automatic was very popular. The preferred setup was the Borg-Warner four-speed. A wide-ratio box was available with the base or 300-bhp engines and close-ratio gearing (2.20:1 first gear) was listed for the top two engines. The standard axle ratio was 3.36:1 with the three speed or Powerglide. The four speeds came with a 3.70:1 final drive, with 3.08, 3.55, 4.11 and 4.56:1 available. The latter was quite rare in production, for obvious reasons.
If the Sting Ray's specifications sound like those of a well-developed, refined sports car, you're right. This car seemed to have all the right stuff, and it proved a resounding success on the showroom floors, on the streets, among the automotive press, and on race tracks. Road & Track magazine had been appreciative of past Corvettes, especially from the standpoint of cost. It stated in 1960 that the Corvette was "unmatched for performance per dollar ...” But its review of the Sting Ray was nearly ecstatic. A few excerpts: "In a word, the new Sting Ray sticks [with] great gripping gobs of traction ... The S-bend was even more fun: every time through it we discovered we could have gone a little faster. We never did find the limit ... As a purely sporting car, the new Corvette will know few peers on road or track ... it ought to be nearly unbeatable."
That verdict was unanimous at all the magazines. In the May 1963 issue of Motor Trend, Jim Wright said: "It's far in advance, both in ride and handling, of anything now being built in the United States. It's completely comfortable without being mushy and it takes a large chuckhole to induce any degree of harshness into the ride. Sudden dips, when taken at speed, don't produce any unpleasant oscillations, and the front and rear suspension is very hard to bottom. There's very little pitch noticeable in the ride, even though the 'Vette is built on a fairly short wheelbase.
Corvette Z06 Stingray Part 2.
At high cruising speeds-and even at maximum speeds nothing but an all-out competition car will equal it in stability. We drove it under some pretty windy conditions and didn't notice any adverse effects from crosswind loading. We thought the old model cornered darn well, but there's no comparing it to this new one. It does take a little different technique, but once the driver gets into it, it's beautiful. Since the 49/51 percent front-to-rear weight distribution, plus the independent rear suspension, gives the Sting Ray an inherent amount of over-steer, the driver will find that on fast comers the car will be doing most of the work through the corner instead of him powering it through." Sports Car Graphic was equally enthusiastic: "The ride and handling are great. We won't elaborate on how great: you've got to drive one to believe it." Car and Driver reported: "The Corvette is now second to no other production sports car in road holding and is still the most powerful."
Even though the engines were unchanged, they seemed more powerful in this wondrous new machine. Wright tested a fuel-injected version with 3.70:1 axle: "On a straight acceleration basis there's very little difference between last year's car and the new one. Our quarter-mile times are within fractions of what they were last year. The only real difference is that the new one doesn't have quite the wheel spin (with stock tires) that the old rigid-axle car had. The 0-30, 0-45, and 0-60 mph steps averaged 2.9, 4.2, and 5.8 seconds, while our average time through the quarter-mile traps was 102 mph, with a 14.5-second ET. Top speed was an honest 130 mph, with the tachometer reading 6,000 rpm. A course longer than the Riverside Raceway backstretch would've produced something very close to the Sting Ray's theoretical top speed of 140-142 mph ... because the engine was still winding when we had to back off."
1963 Corvette Sting Ray convertible
Even some European journalists had to admit that the Americans had a potent piece of machinery. Motor magazine in England noted that its injected test car accelerated faster than anything else in the publication's test history. The Brits downgraded the Corvette for lack of refinement, though Autocar noted surprise that its car didn't use any oil during the test period.
Most of the criticism leveled at the Sting Ray by American magazines concerned either the split rear window on the coupe or the cumbersome business of having to go over the seats to reach the luggage compartment. But the car's many creature comforts met with approval. The contoured bucket seats were I judged comfortable, though soft said they were too low. However, this was part of the low center of gravity that had been Duntov's goal. The seats did move fore and aft, of course, and for the first time the steering wheel could be telescoped in and out allowing a variety of people to find a proper position at the helm. (The column adjustment required the use of a wrench on a collar under the hood.) Instrumentation was also improved and placed where it could be more easily viewed, though the attractive brushed aluminum housings were shiny enough to make glare a problem in certain light conditions.
Several options reflected the desires of Mitchell, Duntov, and others for the new Corvette to be a serious and successful track competitor. Items such as the Alfin brake drums, the handsome (and now rare) aluminum knockoff wheels, stiffer anti-sway bars, metallic brake linings, dual master cylinder and a 36.5-gallon fuel tank all suggested this intent. Together, they made up the Z06 special performance equipment package, offered only on the coupe early in the model year. Four coupes so equipped (except for the knockoffs, which weren't yet ready) made their racing debut at the Los Angeles Times Three-Hour Invitational Race at Riverside on October 13, 1962. At the helm were Dave MacDonald, Bob Bondurant, Jerry Grant and Doug Hooper. This was also the debut of Carroll Shelby's Ford powered Cobra. Though the Cobra would go on to savage the Corvette later, the Sting Ray was well up to the challenge of this Anglo-American hybrid. Three of the cars failed to finish, but the fourth took the checkered flag. Hooper drove the winner, a car owned by Mickey Thompson, who was reported to say, "I don't think it's ever been done before ... a new production car winning the first time out!"
Sting Rays went on to other victories, but it would be the Cobras that would dominate production-class racing in the Sixties. Many Corvette enthusiasts still fault the SCCA for certifying the Cobra as a production car; since it was mainly a low-volume special designed more for racing than road use. Still, Chevy's sports car managed some excellent showings, and its street manners were now so good that it didn't need a racing image to promote sales. Of course, Duntov still held out hopes for the creation of a full competition version, which led to the awesome Grand Sport.
Fuel consumption for the Sting Ray was fairly moderate considering the available horsepower, especially in the fuel injected engines. The Rochester mechanical injection corrected mixture continuously for humidity, temperature and altitude changes, and Motor Trend stated: "This is one of the few high-output engines that can deliver decent gas mileage without being babied. Out on the highway, we averaged slightly better than 18 mpg for one trip where we didn't go above the legal speed limits. On another trip, where the speedometer stayed above 75 and 80 mph a good deal of the time, we saw 16.3 mpg. Whipping around town produced a 13.6 mpg average. For over 700 miles of all types driving, the Sting Ray averaged 14.1 mpg." In addition, all that mileage per gallon at 360 horsepower.
At a base price of $4,393.75, the '63 split-window coupe was relative bargain. Motor Trend's test car, with its top-line engine would have marched from the showroom for $5,322.
When the last '63 rolled off the St. Louis assembly line, Sting Ray production totaled 21,513 units. This was split 49 percent coupes and 51 percent convertibles. More than half of the latter were ordered with the optional lift-off hardtop, continued from previous years. This would be the last time that coupes would be so close to the roadsters in sales until 1969. About 15 percent of 1963 production was equipped with power brakes. A slightly higher percentage had power windows. A slightly lower proportion got power steering. Factory air conditioning, a new option for the 'Vette and priced at $421, was specified by only 278 buyers. Saddle-color leather upholstery, at $80.70, was found on only two percent of the '63s. This was also the first time the 'Vette could be had with genuine cast aluminum knock-off wheels, Kelsey-Hayes 15 x 6-inchers costing $322.80 a set. Thus, the rarest and most collectible Sting Ray would be a split-window coupe with fuel injection, factory air, leather seats, finned aluminum brake drums, the knockoffs, and power brakes, steering; and windows. The aluminum wheels started off the year, by the way, with a two-prong hub, changed later to the more familiar three-prong design.
In looking at Corvette history, the 1963 Sting Ray has a unique distinction: it was the only all new model (apart from engines, which were only a year old anyway) between the original. Motorama car of 1953 and the 1984 generation. While the Sting Ray would undergo a very dramatic body revision just five years after it first hit the streets, the chassis would live on with only modest changes for a full two decades. That it did survive so long bespeaks the sophistication and foresight of its designers, especially Zora Arkus Duntov.
With Corvette sales increasing some 50 percent in a single year, logic dictated that changes for the follow-up 1964 edition would be only evolutionary in nature. As noted, Bill Mitchell gave in to pressure and the coupe's split rear window became one-piece. The two fake air intakes on the hood, which had been inspired by the genuine article on Mitchell's racer, were eliminated, although the indentations remained. The simulated air exhaust vents on the coupe's B pillars became functional, but only on the driver's side. The rocker panel trim lost some of its ribs, and the areas between the ribs were painted black. Wheel covers were simplified, and the fuel filler door gained concentric circles around its crossed-flags insignia. In the cockpit, the color-keyed steering wheel was replaced by one with a simulated walnut rim. Complaints about glare from the instrument bezels were acknowledged, and they were painted flat black on the '64.
An improved ride was among Duntov's original goals for the Sting Ray, and most reviewers judged him successful, especially compared to previous Corvettes. But as the cars rolled up miles, the shock absorbers weakened and owners began complaining about a deterioration in ride quality. Chevrolet attacked the problem with a few suspension refinements. The front coil springs were changed from constant-rate to progressive or variable-rate and were wound more tightly at the top. The leaf thickness in the rear transvers spring was varied from within. The idea was that small bumps would affect only the low-rate areas of the springs, while large bumps would affect the higher areas. The result was to provide a softer ride without sacrificing handling. Shock absorbers were also redesigned toward this end. When subjected to frequent oscillations under near-full vertical wheel travel, such as on very rough roads, the standard '63 shocks tended to overheat, causing the hydraulic fluid to capitate or bubble, losing effectiveness. The 1964 Corvette arrived with a new standard shock. Within the fluid reservoir was a small bag of Freon gas that absorbed heat, thus preventing the fluid from bubbling.
1964 Corvette story soon to come (p122). Ed’s Swap Meet.com thanks you for checking in. Please post your classic car for sale, auto parts for sale, your company, your restoration business with us. Best, JP.