Is there anyone who doesn't like the Corvette Sting Ray? Probably not. This was, after all, the most changed Corvette since Chevrolet first wheeled out its two-seat sports car in 1953, and a stunning piece of work by any standard -- one reason it still dominates the automotive consciousness of a generation. It was also the most popular Corvette up to 1963, setting much higher new sales records in each of its five years save swan-song '67, though it helped to have the first production Corvette coupe as a running mate for the traditional convertible.
There's never been enough of either to go around. Used-car values bottomed out
and headed up less than a decade after the Sting Ray's knock-'em-dead debut,
making this one of the first postwar cars to exceed its original list price on
the collector market. Cynics said the fast turnaround reflected the Corvettes
that followed. In fact, many still regard the Sting Ray as simply the best
Corvette ever.
The Sting Ray was very much stylist Bill Mitchell's car, the first Corvette that
owed nothing to his legendary predecessor, Harley Earl, the founding father of
General Motors Styling. It originated in late 1959 with the XP-720 program that
drew from at least three earlier experimental projects. The first was the
so-called "Q-Corvette," begun in 1957 as a smaller, more radical sports car
sharing a rear transaxle, independent rear suspension, and all-disc brakes with
a line of large, rear-engine sedans being planned for 1960. Only a fastback
coupe was contemplated, and its styling, by the same Bob McLean who'd laid out
the first Corvette, was amazingly predictive of the future of Sting Ray's.
The entire Q-program was soon shelved as too complicated and too costly, but
Corvette engineers led by Zora Arkus-Duntov continued toying with rear-engine
designs even as Chevy introduced one in its first compact, the new-for-'60
Corvair. The advent of that car, plus Duntov's work with the experimental
open-wheel CERV I single-seater, prompted a rear-engine Corvette proposal
designed around the Corvair's air-cooled flat-six power package. Again, however,
GM managers just couldn't see the expense.
Mitchell, meantime, had spirited away the development
"mule" from the abortive Sebring Super Sport project, the long-distance racing
Corvette consigned to the corporate attic after the Automobile Manufacturers
Association's 1957 "anti-racing" edict. Mitchell decided to refurbish the car
and campaign it on his own. Assistant Larry Shinoda adapted Q-Corvette lines to
create a new open body for what Mitchell called the Stingray Special, built in
his bootleg-projects "Studio X" area at the GM Tech Center in Warren, Michigan.
Dr. Dick Thompson, one of the winningest Corvette pilots in Sports Car Club of
America competition, was signed to drive it in C-Modified events, then dominated
by prestigious European machines. "The flying dentist" promptly ran away with
the class championship in 1959 and '60.
Though it never raced as a Corvette, Mitchell's car was
obviously a GM effort. Because it made a big public impression, its styling
figured heavily in XP-720, which sought to deliver a new production Corvette
with more passenger and luggage room, better ride and handling, and even higher
performance.
The starting point was a clean-sheet chassis reflecting lessons learned from all
those earlier experiments. Despite the Corvair's arrival, a conventional
drivetrain layout was never in doubt. Passengers were again placed relatively
far to the rear so that the engine/transmission package could sit behind the
front-wheel centerline for even front/rear weight distribution (which ended up
at 47/53 percent). To further enhance roadability, the wheelbase was trimmed
four inches from that of previous Corvettes, to 98 inches, and the center of
gravity was lowered by having passengers ride within the frame rather than on
top of it. For improved torsional rigidity and optimum driveline placement, the
old Fifties-fashion X-brace frame was discarded for a new ladder-type design
with five crossmembers. At first it was a little too stiff, yielding an
unduly harsh ride. The production unit was made less rigid but still stronger
than needed.
But the big news was independent rear suspension, which Duntov sold to
cost-conscious GM managers by saying it would help sell 30,000 Corvettes a year.
His Sting Ray design employed a frame-mounted differential with U-jointed
halfshafts linked by a transverse leaf spring, much as on CERV I. The spring
bolted to the back of the diff case, which was carried on rubber-cushioned
struts that lessened ride harshness and increased grip, especially on rougher
roads. A control arm extended laterally and slightly forward from each side of
the case to a hub carrier, with a trailing radius rod behind. The halfshafts
functioned as upper control arms. The lower arms also controlled vertical wheel
motion, while the trailing rods took care of longitudinal loads. Being
considerably lighter than Corvette's old solid axle, the new irs brought a
significant reduction in unsprung weight.
Front suspension retained unequal-length upper and lower A-arms on coil springs concentric with the shock absorbers, plus a standard anti-roll bar. Steering remained recirculating-ball, but with a new shock-absorbing damper and faster gearing (19.6:1, previously 21.0:1). Tie rods could be moved to secondary mounting holes in the steering arm to quicken gearing even further (to 17.1:1) and reduce turns lock-to-lock from 3.4 to just 2.9. Hydraulically assisted steering would be a first-time Corvette option except on cars with the two most powerful engines, and would have the faster ratio.
Four-wheel cast-iron drum brakes of 11-inch diameter were also retained, but
they were self-adjusting now and wider at the front to increase effective
braking area and thus stopping power. Sintered-metallic linings were again
optional, and so were finned aluminum ("Al-Fin") drums that made for even less
unsprung weight, plus faster heat dissipation and thus better fade resistance.
Power brakes would be another new Corvette option, along with air conditioning
and leather upholstery.
Evolutionary technical changes included positive crankcase ventilation, a smaller flywheel and, as elsewhere in Detroit, a more efficient electrical alternator instead of the old-fashioned generator.
Chevrolet's masterful small-block V-8, the heart of Corvette power since 1955,
had been enlarged from 283 to 327 cubic inches for 1962. There were four
versions for Corvette, and all were retained for the Sting Ray, along with the
previous three transmissions and six axle ratios. Carbureted engines again
offered 250, 300, and 340 horsepower. As before, the first two employed
hydraulic lifters, mild cam, forged-steel crankshaft, 10.5:1 compression,
single-point distributor, and dual exhausts. The 340 got its extra power from a
bigger four-barrel Carter carb, plus larger intake valves and exhaust manifolds.
A 360-bhp fuel-injected stormer again topped the list. Repeating as standard
transmission was the familiar three-speed manual, but neither it nor the
optional Powerglide automatic was very popular. As ever, the preferred gearbox
was the Borg-Warner manual four-speed, which carried wide-ratio gears with the
250- and 300-bhp engines, close ratios with the other two. Standard final drive
for three-speed and Powerglide cars was 3.36:1. Four-speeders came with a 3.70:1
gearset, but 3.08, 3.55, 4.11, and 4.56:1 were available.
Like the mechanical layout, XP-720 styling was
never in doubt. Even the first tryouts were nothing so much as Mitchell's racer
with a fastback roof a la Q-Corvette. This shape was locked in quickly,
then carefully refined. A functional space buck was completed by early 1960,
coupe styling all but finished by April, and the interior finalized by November.
Only in the fall of 1960 did designers turn to a new convertible and, still
later, its detachable hardtop. Practical matters like glass curvature and
tooling constraints dictated final revisions, but so did aerodynamics. Unusual
for any car in those days, both body types were exhaustively tested as
3/8th-scale models in the Cal Tech wind tunnel.
Though fiberglass body panels were retained as on
previous 'Vettes, the Sting Ray had nearly twice as much structural steel for
greater longevity and quietness. The resulting extra weight was balanced by a
reduction in fiberglass thickness so that both new Sting Rays actually weighed a
bit less than the old convertibles. Passenger room was just as good despite the
tighter wheelbase, and the girded cockpit was stronger and thus safer.
The Sting Ray's most obvious departure from Corvette tradition was the
futuristic new fastback coupe with distinctive "boat-tail" rear deck and unique
split rear window. The latter, a compound-curve "saddleback" derived from
Q-Corvette styling proved quite controversial. Duntov and, later, some
automotive journalists opposed it for hindering driver vision astern. Mitchell
countered that "if you take that off, you might as well forget the whole thing."
He was referring to a full-length "spine" that began with a central hood bulge,
then continued down the roof, through the window, and onto the tail. Mitchell
got his split-window and "backbone," then relented after one year with a
one-piece backlight, having in the meantime created the most collectible Sting
Ray of all.
The rest of the styling package was equally exciting. Quad headlamps were
retained but newly hidden, the first U.S. car with this feature since the 1942
DeSoto. They lived in rotating housings that matched the pointy new front when
the "eyes" were closed. An attractive beltline dip at the door trailing edges
paid homage to Harley Earl. Coupe doors were cut up into the roof, recalling the
abortive Tucker, though they were just as practical for easing entry/exit in a
low-slung closed car. Many disliked the dummy vents on the hood and the coupe's
rear pillars. Functional ones were planned, but were nixed by cost.
Inside was a new interpretation of the
"twin-cowl" Corvette dash used since 1958. One designer recalled that it "was
widely criticized at the time," but defended it as "a very fresh approach to
two-passenger styling." It was certainly more practical, bringing a roomy
glovebox with a proper door, plus an improved heater, new cowl-ventilation
system, and a full set of easily read round gauges dominated by a huge
speedometer and tachometer, all dead ahead of the driver. Corvette's "control
tower" center console was slimmed down but still mounted a clock and an unusual
new vertically situated radio with suitably oriented dial.
Despite its greater luggage space, the Sting Ray lacked a trunklid (also
precluded by cost), which was criticized as much as the coupe's divided
backlight. Cargo had to be wedged in behind the seats; on the convertible, you
also had to disconnect the folded top from its flip-up tonneau panel to gain
access. The spare lived in a drop-down cradle beneath the rear-mounted gas tank,
which now held 20 gallons instead of 16. The familiar big round deck emblem was
newly hinged to double as a fuel filler flap.
GM was still
nominally abiding by the AMA's "racing ban," but this was the best-handling
Corvette yet and Duntov knew it would be raced. Giving competitors the best
possible chance for victory was the rationale behind a new Regular Production
Option, Z06. You first ordered a fuelie coupe with four-speed and Positraction
limited-slip differential, then forked over a formidable $1818.45 in exchange
for the best Al-Fin power brakes with sintered linings, plus heavy-duty front
stabilizer bar, shocks, and springs, and a long-distance 36.5-gallon fuel tank.
The package was listed for the convertible, but no such cars were built.
Handsome cast-aluminum wheels with tri-spinner knock-off hubs were
planned for the Z06 package and as a separate option. But though often shown in
contemporary ads and press photos, they weren't strictly original equipment for
'63. Chevy withdrew them after announcement due to casting problems that made
the wheels porous, causing air leaks. "Good" wheels became available for '64,
and some '63s got them post-purchase, but all Z06 '63s left the St. Louis
Corvette factory on ordinary steel rims.
But such bothers were minor because the Sting Ray was as stunning to drive as it was to behold. Though no faster than a '62 Corvette engine for engine, it had an edge in both traction and handling thanks to the new irs. It was more maneuverable, too, with its tighter wheelbase and faster, easier steering (less weight up front). And somehow, Chevy's high-winding small-block V-8 was better than ever in the Sting Ray. Testing a four-speed fuelie with 3.70:1 gearing, Motor Trend's Jim Wright reported 0-30/45/60-mph times of 2.9/4.2/5.8 seconds and a 14.5-second standing quarter-mile at 102 mph. Considering that, fuel consumption was quite reasonable at 14.1 mpg overall.
Overall, the Sting Ray emerged
as a remarkably balanced and well rounded machine that was both "sports car" and
gran turismo. It vividly impressed hard-boiled auto writers. 'As a purely
sporting car," gushed Road & Track, "the new Corvette will know few
peers on road or track...." Echoed Sports Car Graphic: "The ride and
handling are great.... You've got to drive one to believe it." Car and
Driver judged the Corvette "now second to no other production sports car in
roadholding and [it's] still the most powerful." Car Life simply gave the
Sting Ray its annual Award for Engineering Excellence.
Better still, the Sting Ray maintained Corvette tradition by offering terrific value for the money. A split-window coupe with the fuelie engine and a few other goodies delivered for around $5300 -- a sensational deal. (When you consider inflation, it would be about the price of a tame Japanese family sedan today.) It's a lot different now: A prime-condition split-window easily fetches $40,000-plus, about the same price as a new Corvette.
Sales reflected the Sting Ray's exciting combination of sexy sophistication and
world-class all-around performance. At 21,513 units, model year '63 production
was up 50 percent over 1962, itself a Corvette record. Interestingly, the total
divided almost evenly between the ragtop and the new coupe, though the latter
would not sell as well again in the Sting Ray years, which might have pleased
Mitchell.
Though change hardly seemed needed after this enthusiastic reception, the Sting Ray was nevertheless pleasantly tidied up for 1964. Besides a one-piece rear window for the coupe, Chevy cleaned up appearance by erasing the two fake hood intakes (but not their indentations), making the coupe's fake left-rear-pillar vent functional, and simplifying rocker trim and the standard wheel covers. Steering wheels switched from color-keyed to simulated walnut, and instrument bezels changed from chrome to flat black to eliminate glare.
Aiming at a still-smoother ride, Chevy fitted
progressive instead of fixed-rate front coil springs wound more tightly at the
top, and a rear transverse spring whose leaf thickness varied from within. The
result was a wider damping range that better absorbed disturbances without
compromising handling. Shock absorbers gained a small bag of cooling freon gas
to prevent the fluid bubbling and consequent loss of damping that plagued the
'63s. Answering complaints about noise were more sound insulation, revised body
and transmission mounts, and additional bushings in the shift linkage.
Drivetrain choices stayed the same, but a big new Holley carb and
high-lift camshaft brought the solid-lifter 350-bhp engine to 365 bhp; the
360-bhp fuelie went to 375. Transmissions were ostensibly the same, too, but the
Borg-Warner four-speeds gave way to a similar pair of manuals from GM's Muncie,
Indiana, transmission plant. Originally a Chevy design and already being used on
other GM models, the "Muncie" featured stronger synchronizers and wider ratios
for better durability and driveability. Positraction, still a bargain extra at
$43.05, went into more than 80 percent of 1964 production. The sintered-metallic
brakes were much costlier -- a whopping $629.50 -- but now included the Al-Fin
drums.
Coupe production dropped for 1964, but convertible
sales more than compensated. The grand total of 22,229 was yet another Corvette
high, if up only a little from banner '63. The Sting Ray was again tidied up for
'65 -- and muscled up in a big way. Styling alterations comprised a smoothed-out
hood, a trio of working vertical exhaust vents in the front fenders (replacing
non-functional "speedlines"), and restyled wheel covers and rocker moldings.
Optional four-wheel disc brakes made news. A four-piston design with two-piece
calipers and finned rotors, they upped total swept braking area to 461 square
inches, a notable advance on the old drum system's 328 square inches. Per
pending federal regulation, Chevy fitted a new dual master cylinder with
separate fluid reservoirs for the front and rear lines. Road testers roundly
applauded these changes. Sports Car Graphic found the discs "a distinct
pleasure to operate .... Repeated stops from 100 mph produced no deterioration
in braking efficiency ...." Diehards could still have drums as a $64.50 credit
option, but discs were slipped into all but 316 of the 23,562 Corvettes built
that model year.
The Sting Ray hadn't lacked for horsepower, but some customers craved more. Chevrolet obliged them at mid-model year '65 with the first Corvette big-block. Officially titled Mark IV but marketed as the "Turbo Jet," this new 396-cubic-inch wedge-head engine immediately ousted the fuelie small-block from the engine roster. It dated from early 1963 and the so-called "mystery" 427 that showed up for the Daytona 500. Retained for production was "porcupine" valvegear -- pushrods set at odd angles. Hydraulic lifters, four-barrel carb, and 11:1 compression added up to a thumping 425 bhp. Premium features included impact-extruded alloy pistons with chrome rings, double-snorkel air cleaner, oversized sump, and a forged crankshaft cross-drilled to lubricate the rod bearings through a full 360 degrees.
The big-block 'Vette was in short supply during '65, but it was hardly short on
go-power. Even with the mild 3.70:1 rear axle it could do standing quarter-mile
times of around 14 seconds at 102-104 mph and sail on to nearly 140 mph. To
handle its brute force, Chevy threw in stiff front springs and sway bar, a
special rear sway bar, super-duty clutch, and a larger radiator and fan. An
aggressive-looking hood bulge and optional side-mounted exhaust pipes identified
the beast at rest. Though it weighed some 650 pounds, the big-block gave the
Sting Ray even better weight distribution, a near-perfect 51/49 percent.
But Ford had an impressive 427 V-8 that Carroll Shelby was stuffing
into his sparse two-seat Cobras. Corvette needed a 427 to keep pace, and it got
one for 1966. This bored-out 396 delivered 390 bhp on 10.25:1 compression or 425
bhp via an 11:1 squeeze, larger intake valves, solid lifters, and a large
four-barrel Holley on an aluminum manifold. Though the latter had the same
horsepower as the 396, both 427s packed a lot more torque -- 460 lbs/ft. Of
course, horsepower was often understated in those days in deference to insurance
companies. Here, 420 and 450 bhp were closer to the truth. Positraction and the
close-ratio Muncie four-speed were mandatory options with either 427, but you
did get an uprated suspension (basically the 396 package) as well as stouter,
shot-peened halfshafts and U-joints, and a higher-capacity radiator and sump.
Any 427 Sting Ray was an incredible performer. With the short
4.11:1 gearset, Sports Car Graphic's example did 0-60 mph in a nearly
unbelievable 4.8 seconds and ran up to 140 mph. The modest 3.36:1 axle made
things only a bit less sensational; Car and Driver reported 0-60 in 5.4
seconds and a standing quarter-mile of 12.8 seconds at 112 mph.
Big-blocks made 327s less necessary, so '66 offerings were cut to the
basic 300- and 350-bhp versions. The small-blocks were still arguably the best
all-around Sting Ray engines. They required premium fuel and lacked the 427's
rocket-like thrust, but they remained mighty impressive.
Otherwise, 1966 was a stand-pat year save an eggcrate grille insert to
replace horizontal bars and a coupe shorn of its roof extractor vents. The
relative lack of change reflected plans for a new 1967 Corvette and not a
fall-off in Sting Ray demand. Indeed, 1966 ended up being another record-busting
year, with volume rising to 27,720 units.
But 1967 brought yet
another Sting Ray, owing to last-minute development problems with its erstwhile
successor. Not that anyone really minded, for this was the best Sting Ray yet.
It was certainly the cleanest. Five small front fender vents replaced the three
larger ones, and flat-finish rocker moldings conferred a lower, less chunky
appearance. New, and thus unique to the '67 Sting Ray, was a single backup light
above the license plate. The lovely cast-aluminum knock-offs were no longer
around, but wheel covers gave way to neat, six-inch-wide slotted "Rally" wheels
with chrome beauty rings as standard equipment. Upholstery was shuffled, the
handbrake migrated from under the dash to between the seats, and the
convertible's optional hardtop was offered with a faddish black vinyl cover.
Both small-blocks and the 390-bhp big-block (hulking beneath a redesigned hood
scoop) were unchanged, but there were two new 427s with triple two-barrel carbs
belting out 400 and 435 bhp. The latter, RPO L71, boasted solid lifters and
transistorized ignition. It was also available with special aluminum heads
(instead of cast iron) and larger exhaust valves as RPO L89, though with the
same grossly understated horsepower.