The Triumph
Spitfire is a British front-engined, rear-wheel drive, two-passenger
convertible sports car introduced at the London Motor Show in 1962 and
manufactured between 1962-1980. Styled for Standard-Triumph in 1957 by Italian
designer Giovanni Michelotti, the Spitifire was manufactured for the duration
of its production at the Standard-Triumph Canley works — and evolved over a
series of five production iterations, with a approximately 315,000 manufactured
over 18 years.
Developed
on a shortened variant of the Triumph Herald saloon/sedan's chassis, the
Spitifire shared the Herald's running gear and Standard SC engine. The design
used body-on-frame construction, augmented by structural components within the
bodywork and rear trailing arms attached to the body rather than the chassis. A
manually deployable convertible top, substantially improved on later models,
provided weather protection and a bespoke hard-top was available as a factory
option.
Popular in
street and rally racing, Spitfires won numerous SCCA National Sports Car
Championships in F and G Production classes; won its class at the 1964 Tour de
France rally, coming in second overall, and won the 1964 Geneva Rally. In 1965,
a Spitfire won its class in the Alpine Rally.
The
Spitfire nameplate refers to the World War II fighter plane of the same
name.[7] Assembled at Canley in August 1980 shortly before the factory closed,
the last Spitfire was an Inca Yellow UK-model including the factory hardtop and
overdrive options. Never sold to the public, it remains on display at the
British Motor Museum.
The
Spitfire was conceived by Standard-Triumph to compete in the small sports car
market against the Austin-Healey Sprite. The Sprite had used the drive train of
the Austin A30/A35 in a lightweight. The Spitfire used mechanicals from the
Herald saloon/sedan. Where the Austin A30 used monocoque construction, the
Herald used body-on-frame — a chassis Triumph was able to downsize, saving the
cost of developing a completely new chassis-body unit.
Giovanni
Michelotti, who had designed the Herald, styled the bodywork, which featured
wind-up windows (in contrast to the Sprite and Midget, which used side
curtains) and an assembly of the bonnet/hood and wings/fenders that opened
forward for engine access. The Spitfire's introduction was delayed by its
company's financial troubles in the early 1960's and was subsequently announced
shortly after Standard Triumph was taken over by Leyland Motors. When Leyland
officials, taking stock of their new acquisition, found Michelotti's prototype
under a dust sheet in a factory corner, it was quickly approved it for
production.
Spitfire 4 or Mark I (1962–64)
The
production design changed little from the prototype: the full-width rear bumper
was replaced by two part-bumpers curving around each corner, with overriders.
Mechanicals derived from the Herald saloon/sedan, with the notable addition of
front disc brakes. Bodywork was bolted to the much-modified Herald chassis, the
outer rails and the rear outriggers having been removed; with structural outer
sills to stiffen the overall design.
The engine
was an 1,147 cc (70.0 cu in) four-cylinder with a pushrod OHV cylinder head and
two valves per cylinder, using twin SU carburettors. The Herald's rack and
pinion steering and coil-and-wishbone front suspension carried over, having
derived from systems used by the former Alford & Alder company that had
been acquired by Standard-Triumph in 1959.
Rear
suspension was by a single transverse-leaf swing axle,[8] an arrangement, that
unless ameliorated by any of several options, can allow rear tires to undergo
large camber changes during fast cornering, leading to oversteer – a
dynamically unstable condition in which a vehicle can lose control and spin. As
did many manufacturers who used a swing axle arrangement (e.g., Mercedes,
Renault, Volkswagen]], Triumph would later modify the rear suspension. In 1970,
the rear suspension was decambered, by incorporating what Triumph called a
"swing spring". One leaf was eliminated from the stack and only the
bottom leaf was attached rigidly to the differential. The remaining leaves were
mounted to pivot freely — thereby eliminating the worst characteristics of the
original swing-axle design.
The
Spitfire was an inexpensive small sports car and as such received rather basic
trim by today's standards, including rubber mats and a large plastic steering
wheel. It was nonetheless considered fairly comfortable at the time, as it had
roll-down windows and exterior door locks, as well as relatively full
instrumentation. These early cars were referred to both as "Triumph
Spitfire Mark Is" and "Spitfire 4s",[1] different from the later
Spitfire Mark IV. The "Spitfire 4" name indicated the possibility of
the appearance of a six-cylinder version.
In UK
specification the in-line four produced 63 bhp (47 kW) at 5,750 rpm, and 67 lb⋅ft (91 N⋅m) of torque at 3,500 rpm. This gave
a top speed of 92 mph (148 km/h), and a 0 to 60 mph (97 km/h) acceleration in
16.4 seconds. Average fuel consumption was 31 mpg.
For 1964 an
overdrive became optional to the four-speed manual gearbox.[4] Wire wheels and
a hard top were also available.
An
all-monocoque construction derivative of the Spitfire with pop-up headlamps,
named the Triumph Fury, was proposed with a single prototype being built.
Spitfire Mark II (1965–67)
In March
1965 the Spitfire Mark II launched with a retuned engine, featuring a revised
camshaft profile, water-heated intake manifold, and tubular exhaust manifold,
increasing power to 67 bhp (50 kW) at 6,000 rpm. The coil-spring design clutch
of the Mark I was replaced with a Borg & Beck diaphragm spring clutch;
North American models retained the coil-spring housing and were also equipped
with ACDelco distributors. Exterior trim featured a new grille and badges, and
the interior featured revised seats, covering most exposed surfaces with rubber
cloth. Carpeting replaced the original moulded rubber floor mats.
Its base
price was £550; the Austin-Healey Sprite's was £505 and the MG Midget's £515.
Top speed was claimed to be 96 mph (154 km/h) and its 0–60 mph time of 14.8
seconds was considered "lively". The factory claimed that at highway
speeds (70 mph (110 km/h)) the car achieved 38.1 miles per imperial gallon
(7.41 L/100 km; 31.7 mpg‑US).
Spitfire Mark III (1967–70)
The Mark
III, introduced in March 1967, was the first major facelift to the Spitfire.
The front bumper was raised in response to new crash regulations, and the front
coil springs were slightly raised. Slightly revised bonnet pressings were
carried over. Rear overriders were deleted and bumper mounted reversing lights
became standard (initially as two separate lights on either side of the number
plate, latterly as a single light in a new unit above the number plate). The
interior received a wood-veneer instrument surround and a smaller, 15-inch,
wire spoked steering wheel. A folding hood replaced the earlier, more complicated
design. For most of the Mark III range, the instrument cluster remained
centre-mounted (as in the Mark I and Mark II), easily accommodating right-hand
and left-hand drive versions.
The 1,147
cc engine was replaced with a bored-out 1,296 cc unit (the bore increasing from
69.3 mm (2.73 in) to 73.7 mm (2.90 in), stroke retained at 76 mm (3.0 in)), as
fitted on the new Triumph Herald 13/60 and Triumph 1300 saloons. A new quieter
exhaust gave a sweet distinct note and reduced cabin noise. In SU twin-carburettor
form, the engine put out a claimed 75 bhp (56 kW) at 6,000 rpm, and 75 lb⋅ft (102 N⋅m) of torque at 4,000 rpm, and made
the Mark III a comparatively quick car by the standards of the day.[citation
needed] Options included wire wheels, factory hard top and a Laycock de
Normanville overdrive. The Mark III was the fastest Spitfire yet, achieving 60
mph (97 km/h) in 13.4 seconds, and reaching a top speed of 95 mph (153 km/h).
Average fuel consumption was 33mpg. The Mark III continued production into
1971, well after introduction of the Mark IV.
On 8
February 1968, Standard-Triumph general manager George Turnbull drove the
100,000th Triumph Spitfire off the Canley production line. More than 75 per
cent of this number had been exported outside the UK, including 45 per cent to
the US and 25 per cent to mainland European markets.
The 1968
model featured dual system (aka tandem) brakes with a brake failure warning
device. The engine used a revised camshaft and a distributor with idle speed
ignition timing retarded to address emissions. The twin SU carburettors now
included overrun valves in the throttle discs and anti-tampering features on
carburettor fuel-air mixture nuts.
Starting in
1969, US-bound models were "federalized" to comply with safety and
emissions regulations. A reduced compression ratio of 8.5:1 resulted in a
slight decrease in power (68 bhp) and 73 ft-lbs of torque. However, the 0–60
time of 14 seconds was still faster than the Mark II. The instrument panel was
moved in front of the driver, and new seats were introduced with integrated
headrests to help against whiplash. Cosmetically, the wood dash was replaced
with a matte black finished assembly intended to imitate an aircraft cockpit.
The Mk.
III's final production year (1970) included an integrated rear reverse and
license plate lamp, side lamps at the front and rear and new badging. The
separate "Triumph" letters on the front of the bonnet were removed
and "Triumph" and "Spitfire" rectangular badges were used
in the front, rear sides and rear. A limited number of U.S. market 1970s were
adorned with an RAF style "Spitfire" badge (U.K. models had a plain
badge without the RAF roundel) that rested in the right corner (car opposing
point of view) of the bonnet. Additional exterior changes introduced included a
zip up rear window, black radiator grille and a black (vs body colored)
windshield surround. Full wheel covers of two styles were used including the
1969 introduced model with "SPITFIRE" circumscribing the hub and a
unique derivative without the branding. Interior changes included a steering
column mounted ignition switch, a key-in-ignition warning buzzer, driver's side
under-dash courtesy lamp and a new black spoked steering wheel. Under the
bonnet, some markets had the twin SU carburettors replaced with a single
Zenith-Stromberg carburettor.
Spitfire Mark IV (1970–74)
The Mark IV
featured a redesigned rear design similar to the Triumph Stag and Triumph 2000
models, both also designed by Michelotti. The front end was revised with a new
bonnet pressing eliminating the weld lines on top of the wings/fenders, door
handles were recessed, the convertible top received squared-off corners. The
interior was revised to include a full-width dashboard, with instruments ahead
of the driver rather than over the centre console, initially finished in black
plastic and beginning in 1973 finished in wood.
The engine
was now rated at 63 horsepower for UK market, employing the 9:1 compression
ratio and twin SU HS2 carburetors. The less powerful North American version
continued to use a single Zenith Stromberg carburetor and an 8.5:1 compression
ratio) due to the German DIN system; the output was the same for the early Mark
IV. Performance was slower than the Mark III due to its weight increase taller
3.89:1 final drive as opposed to the earlier 4.11:1.
The Mk. IV
engine displaced 1,296 cc (79.1 cu in) throughout the production run, and in
1973 received larger big-end bearings to rationalize production with the TR6
2.5-litre engines. The engine was also detuned to meet new emissions
regulations. With the overall weight also increasing to 1,717 lb (779 kg)
performance dropped, with 0 to 60 mph (0 to 97 km/h) now in 15.8 seconds and
top speed reduced to 90 mph (140 km/h).[1] Fuel economy was 32 mpg‑imp (8.8 L/100 km; 26.6 mpg‑US). The
gearbox gained synchromesh on its bottom gear.
A revised hardtop
became also available, with rear quarter-lights and a flatter rear screen.
Importantly,
the heavily criticized rear suspension was decambered, incorporating what
Triumph called a "swing spring". One leaf of the suspension
"stack" was eliminated and only the bottom leaf was attached rigidly
to the differential. The remaining leaves were mounted to pivot freely —
eliminating the worst characteristics of the original swing-axle. This was a
different approach than that taken with the Triumph GT6 Mk II (GT6+) and
Triumph Vitesse Mark 2, both of which received new lower wishbones and Rotoflex
half-shaft couplings. The result on all these cars was improved handling.
The Mark IV
went on sale in the UK at the end of 1970 with a base price of £735.
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