Rigger (pronounced rig-er)
(1) A
person who rigs.
(2) A person
whose occupation is the fitting of the rigging of ships.
(3) A person
who works with hoisting tackle, cranes, scaffolding etc (the protective or
supporting structures on or around construction sites).
(4) A mechanic
skilled in the assembly, adjustment, and alignment of aircraft control
surfaces, wings, and the like (eg parachute rigger); a person skilled in the
use of pulleys, lifting gear, cranes etc.
In
rowing, rowing a bracket on a racing shell or other boat to support a
projecting rowlock or other fixed fulcrum.
(6) In
digital animation, one whose occupation is to outfit a computer model with
controls for animation.
(7) One
who rigs or manipulates (an election, a market etc).
(8) A
plastic bottle of beer, typically between with a volume between 1.0-2.5 litres
(1-2.6 quarts) (New Zealand).
(9) In
(usually graphic) art, a long, slender, pointed sable paintbrush for making
fine lines etc; said to be so called from its use for drawing the lines of the
rigging of ships.
(10) In
the role-playing behavior of sadomasochism, a person who applies functional or
artistic rope or strap bondage to another person's body.
(11) A
cylindrical pulley or drum in machinery.
(11)
One whose occupation is to lift and move large and heavy objects (such as
industrial machinery) with the help of cables, hoists, and other equipment.
1490s:
The construct was rig + -er. Rig was
from the Early Modern English rygge,
probably of North Germanic origin and related to the Danish & Norwegian rigge (to bind up; wrap around; rig;
equip), the Swedish dialectal rigga
(to rig (harness) a horse) and the Faroese rigga
(to rig; to equip and fit; to make function”). The source was perhaps the Proto-Germanic rik- (to bind), from the primitive
Indo-European rign- reig-, & reyg- (to bind) or it was related to the
Old English wrīhan, wrīohan, wrēohan & wrēon (to bind; wrap up; cover) which are linked also to wry (to
cover; clothe; dress; hide). The late
fifteenth century verb rig was originally nautical in the sense of "to fit
(a ship) with necessary tackle; to make (a ship) ready for sea" and gained
the extended sense of "dress, fit out with, furnish with, provide (with
something) emerged in the 1590s; that of "to adjust, put in condition for
use, set in working order" is from circa 1625.
The
slang meaning "pre-arrange or tamper with results" is attested from
1938, although the noun rig (a trick, swindle, scheme) had been used as early
as (1775) and, apparently unrelated was the meaning "sport, banter,
ridicule" dating from 1725. The
phrase “to rig the market” was used, firstly in stock exchange c=slang and
later more generally to convey the idea very familiar in modern times: "raise
or lower prices artificially to one's private advantage". One use as a verb which faded was that
meaning "ransack", from the 1560s.
It’s strange rig & rigger took that long apparently top evolve given
rigging was known as a verb meaning "action of fitting (a ship) with
ropes” circa 1400 and as a noun meaning "the ropes that work the sails of
a ship" from the 1590s. It may be
rig and rigger in this context existed in oral use. The use in nautical & naval architecture
to describe the "distinctive arrangement of sails, masts etc on a ship;
the characteristic manner of fitting the masts and rigging to the hull of any
vessel," without regard to the hull is documented from 1769 although a
number of sources insist the first use was in 1822, probably because that’s the
earliest known reference in Admiralty papers.
Use
extended to costumes, and clothing outfits (especially if as a fanciful
description) by 1843. In engineering, it
was widely used to describe just about any creation added for some purpose but
was by 1831 most associated with horse-drawn vehicles and this was later
adopted to refer to trucks, buses etc, a use still common today, especially for
large trucks. In oil extraction, the
apparatus used for well-sinking was known as a rig as early as 1875. Rig was 1570s slang for “a wanton girl or
woman" which, although long obsolete had had the odd idiosyncratic
revival; it was probably related to the also obsolete use from the same era
describing "to play the wanton; to romp about". As a noun, a rigger by 1610 was "one who
rigs ships", that sense later adopted to describe aircraft mechanics
(1912) and those employed on oil rigs (1949).
The –er
suffix was from the Middle English –er
& -ere, from the Old English -ere, from the Proto-Germanic -ārijaz, thought
usually to have been borrowed from Latin –ārius and reinforced by the
synonymous but unrelated Old French –or & -eor (the Anglo-Norman variant
was -our), from the Latin -(ā)tor,
from the primitive Indo-European -tōr. The –er suffix was added to verbs to create a person or thing that
does an action indicated by the root verb; used to form an agent noun. If added to a noun it usually denoted an
occupation.
“Square-rigged” ships are those with (approximately) square sails rigged onto horizontal spars attached to perpendicular masts, sitting therefore square to the keel. The spars are known also as yards and their tips, beyond the last point of attachment (or stay) are called yardarms, the part of a rig associated with the phrase “hung (ie hanged) from the yardarm”, in folklore the Admiralty’s preferred means of executing death sentences though practiced less frequently than the legend suggests. The square-rig formation evolved as the standard ocean-going form because, when sailing downwind, it’s aerodynamically the most efficient shape which survived into the steam age, many of the early steam-ships (including naval vessels) constructed as hybrids which combined powered propulsion with square-rigged sails. To reduce running costs and carbon emissions, there’s now a renewed interest in using sails (or sail-like structures) on commercial vessels to augment the power from oil-based engines. Square was from the Middle English square, sqware & squyre, from the Old French esquarre & esquerre, (which persists in modern French as équerre), from the Vulgar Latin exquadra, the construct being ex- (from Middle English, from words borrowed from the Middle French, from the Latin ex (out of, from), from the primitive Indo-European eǵ- & eǵs- (out)). It was cognate with the Ancient Greek ἐξ (ex) (out of, from), the Transalpine Gaulish ex- (out), the Old Irish ess- (out), the Old Church Slavonic изъ (izŭ) (out) & the Russian из (iz) (from, out of). The “x” in “ex-“, sometimes is elided before certain constants, reduced to e- (eg ejaculate)) + quadro, from quadrus (square), from quattuor (four).
The
square-rigger MGs
The “square rigger” sports car was one made
in the style which evolved in the 1920s and 1930s, characterized by the
upright, angular lines of its many disparate parts, the point of comparison
being the classic big ships of the sail age.
The term came into use in the immediate post-war years to differentiate
these old-style sports cars from the new, modernist generation, typified by the
Jaguar XK-120, which featured lower profiles and curvaceous, flowing
lines. The term is thus often used
casually to apply to any sports car of the old, pre-war style.
In the post-war years, the
term “square rigger” came most to be associated with the T series MGs. Replacing the P series which in two models
had run between 1934-1936, the T series was, excluding the war years, in production between 1936 and 1955,
the year Citroën introduced the DS which provides a comparison as amusing as
the XK-120. Somewhere during those two
decades the cars descended into obsolescence but their attraction lay in
their charm and the sheer entertainment they delivered, offering an intimate
and tactile experience which belied their miniscule power and performance which
was, at least in a straight line, modest when compared even to mundane family
cars of the era.
MG PA
Midget (1934-1935, 1973 built)
The P series Midget replaced the rather more exotic J series and although
the relationship to previous models was obvious, the P was well-received and thought
much improved. The new overhead camshaft
(OHC) 847 cm3 (52 cubic inch) engine attracted particular praise,
the revised lubrication and induction system delivering a willing and lively
character well suited to a sports car.
Knowing many customers would use them for competition, MG installed
a strengthened four-speed gearbox and heavy-duty clutch, drivers assisted in
their ability to harness the additional performance by brakes fifty percent
larger. It featured also one of the
first safety innovations (a thing that would in coming decades become an
accelerating trend), a flat-fold windscreen made from toughened
non-discolourable “Triplex safety glass".
The P series was offered in the colors
which would come to be associated with the marque (Ulster Green, Dublin Green,
Oxford Blue, Cambridge Blue, Carmine Red & Saratoga Red) but the most
popular choice remained gloss-black. The
standard factory bodies were the two-seater roadster and four-seat tourer but specialist
coachbuilders made available more elaborate drophead coupés (DHC) although the style most memorable was Allingham’s Airline Coupé although, being as expensive as many
larger vehicles, few were ordered. At
the time of release, the factory listed the two seater at Stg£220, the four seater
an additional Stg£20; the Airline cost Stg£290.
Unlike
many of its predecessors, the factory didn’t envisage a competition programme
for the P series but a three-car team was entered in the 1935 24 hour Le Mans race. Remarkably,
the drivers were six young ladies, bright young things soon dismissively dubbed
"The Dancing Daughters" by
the even then nasty British tabloids, the reference being to a popular BBC
radio programme of the time (a broadcast of a troupe of teenage tap-dancers, perhaps
a challenging concept for radio although, in the studio, the girls were costumed skimpily “to get the atmosphere”). They
attracted much publicity but little success, the cars under-powered for such a
circuit.
MG PB
Midget (1935-1936, 525 built)
The Le Mans experience in part prompted the more powerful PB which
was introduced in 1935, the engine was enlarged to 939 cm3 (57 cubic
inch) and a close ratio gearbox was fitted. There were detail changes too, one
of which the consequence of an early example of environmental legislation. In 1935, fearing an ancient species was under
threat, the US government banned the export of Sequoia redwood timber so the
PB’s dashboard was instead finished in the more familiar burr walnut. Very much a transitional model, the PB was available
only briefly but its debut depressed interest in the PA to the extent that not
even a substantial price was enough of an inducement to buyers so the factory
converted the two-dozen odd remaining PAs to PBs, both variants sold for the same Stg£222. Production of the PB ended in February
1936.
MG TA
Midget (1936-1939, 3,003 built)
Corporate restructurings are nothing new and nor is the tyranny of
the cost-accountant. In 1935, the MG Car
Company was sold to Morris Motors and in the inevitable agonizing reappraisal
which ensued, MG lost its autonomy and became a corporate badge and one
expected to deliver a better return on capital: profits had to be higher. The first sacrifice was the competition
department, followed almost immediately by the MG design office and the
cancellation of the spirited little OHC engine which had given the PA & PB
so much of their sporting character. It
was a harbinger, a rationalization which would spread and over decades drive almost
all the UK’s motor industry to extinction.
Under new management, the design imperatives were now profitability, simplicity
of production and uniformity in parts to maximize interchangeability between
ranges.
The purists were thus not hopeful but the T series, released in
1936 was the first in a successful line which would be in production for a
dozen-odd years, the run till 1955 interrupted only by six war years during
which MG’s industrial capacity was given over to military needs. The T might not have had the OHC engine but
the overhead valve (OHV) pushrod unit which replaced it, although borrowed from
a pedestrian little saloon, was a larger 1292 cm3 (79 cubic inch)
and generated some 50 horsepower, a useful increase over the 36 & 43 the P
series engines had managed and delivered it in a more effortless manner than
its smaller predecessors which actually made it more suitable for both the road
and in competition. Longer and wider,
the T was much more spacious and the hydraulic brakes were a welcome addition,
all for the same Stg£222 as the PB.
The T series made the Midget
suddenly civilized although, as part of the corporate rationalization, factory
coachwork was limited to a single two-seat roadster but separate chassis were
still supplied to coachbuilders and Tickford (the brand of Salmons and Sons (1830)), produced some two hundred and
fifty elegant DHCs with such luxuries as wind-down windows,
full carpeting and a clever convertible top which could be closed, partially
open or fully thrown back. The Airline
style was reprised by Allingham, Whittingham & Mitchel and Carbodies and although
much-admired, being still expensive, only a handful were built. Despite the misgivings, the T proved a great
success and was built until 1939 when it was replaced by the TB which included
a new engine which would become one of the most storied in MG’s history: the XPAG.
MG TB
Midget (1936, 379 built).
By May 1939, war clouds were gathering over Europe and Finnegans Wake by James Joyce
(1882–1941) was published. Into this strange and uncertain environment, MG released the TB, visually apparently as little
changed from the TA as the PB had been from its predecessor but under the
louvered bonnet now sat the new XPAG engine which would until 1955 power just
about every MG made and provide numerous builders of race cars with a light,
robust and tunable power-plant, one which would see some of the specials it
powered top 200 mph (320 km/h). Over the
years, extraordinary power outputs were achieved, the tough little engine able
to withstand supercharging at pressures which broke many others. Totally new, although a slightly smaller 1250
cm3 (76 cubic inch), there was now a bigger bore which lent itself
to a sportier state of tune but, under the dopey calculation of the time, attracted a
higher tax-rate. With the introduction
of the TB, the designation TA was applied to the earlier car which hitherto had been
known simply as the T series, the same act of retrospective re-christening which had turned P into PA. The TB was priced
at Stg£225 for the 2 seater and Stg£270 for Tickford’s DHC but there would be no more
of the exquisite Airlines.
The XPAG restored some of the character of the old OHC engine, the
bigger bore and shorter stroke delivering the maximum 55 horse power at 5,250
rpm against the 4,500 rpm of the TA, performance generally improved in all
aspects and made easier to exploit with the fitting of a new four-speed gearbox
which included synchromesh on all but the lowest ratio. The TB was in production for only a few
months before the declaration of war in September; the brochures for the 1940
model-year were actually ready for printing and the range had been
announced when production was abruptly halted after 379 TBs had been
completed. Rapidly, the Abingdon factory
was cleared of all the machinery of car assembly and devoted for the
duration to parts for aircraft, machine guns and the servicing of tanks and
trucks. In hibernation for six years,
the TB would return in what would prove to be a new world and it would be
called the TC.
MG TC (1945-1949,
10,001 built).
On both sides of the Atlantic, the cars released in the early post-war years
were almost all barely revised versions of those last available before the
outbreak of hostilities. The MG TC, the
first of which left Abingdon in 1945 actually was structurally more different
from the TB than most of the cars of 1945-1946 were from their predecessors
because the passenger compartment had been widened by four inches (100 mm),
creating more interior space without the need otherwise to alter the body or
chassis. Other than that and some detail
mechanical and electrical upgrades, it was essentially a re-birth of the same
basic design as the TA of a decade earlier.
Despite that, just resuming production to the extent of the few dozen
examples completed before the end of 1945 was something of an achievement given
the chronic shortages of steel and other raw materials or components.
Immediately, it was an outstanding success.
The UK’s new government understood the parlous state of the nation’s
finances and extorted the manufacturing sector with the simple mantra “export
or die” and MG responded, much early TC production allocated to the export
trade. The volume of sales to the Commonwealth’s
southern dominions (Australia, New Zealand & South Africa) had been expected
because these had been receptive markets in the pre-war years but what was
surprising was the demand from the United States and Canada, triggered it was
suspected by the number of returning servicemen who had so enjoyed or at least
yearned for the little sports cars during their time in the UK. Although only 2000 of the 10,001 TCs made
went to the US, the interest was enough for the factory to do a run of
US-specific models (still all right-hand-drive) and it was the TC which whetted
the American appetite for small sports cars and in the 1950s, MG would benefit
from what became something of a craze, one which the square-riggers and their
successors would for decades exploit.
MG TD (1949-1953,
29,644 built)
The TD was the most popular of the T series and was the car which both
established the brand in the US and encouraged others to realize the sports car
craze was real and thus a market segment to explore. From what General Motors initially regarded
as the improbable success of the TC and TD, would come first the tentative toe
in the water that was the Chevrolet Corvette show-car and later the long line
of production cars which, over eight generations, continues to this day. The TC however was, even before it was
discontinued in 1949, a museum-piece, if an entertaining one, and it was clear
that for MG further to succeed in the US market would require a more modern
interpretation of the sports car. The
budget was limited but the culture of simplicity of production and uniformity in
parts to maximize interchangeability between ranges now proved advantageous, a
small team allocated to develop a prototype using mostly what fell immediately
to hand. In what was a master-class in
improvisation, they shortened by five inches (127 mm) and then stiffened the
chassis of a MG YA saloon, grafted on an independent front suspension & rack
and pinion steering, made the changes necessary to ensure it could easily be
made with either left or right-hand drive and overlaid a (slightly) modernized rendering
of the TC’s body. The design team would
have preferred to create something more sophisticated and certainly something
which looked more contemporary but, given the constraints under which they
worked, the TD was a good result, both as a piece of engineering and, more
critically, one that made commercial sense.
Underneath, the changes were transformative and they needed to be. The TC’s platform was little changed from the
cars of the 1930s, themselves just refinements of a decade-old concept and
while antiquated even compared to its stop-gap contemporaries of 1945-1949, it looked
prehistoric against the new generation models of the early 1950s. The TD’s saloon-based chassis was hardly
innovative but was rigid and well-executed with a modern arrangement for the
independent front suspension and a rear-end which accommodated additional
travel by sweeping the frame up over the axle instead leaving it underslung. The XPAG engine differed in
being derived from that used in Y type so included its improvements to
lubrication and the attached accessories.
The most obvious change was to the body, substantially revised for the
first time since 1936 and, while the stylistic legacy was apparent, was
considerably wider and thus more spacious.
Structurally, the engineering was carried-over, body panels still
mounted on the traditional wooden frame of English ash.
A mix then of old and new as many products are. Even though not one body-panel was unchanged
and the interior fascia was new, the aesthetic was entirely square-rigger with cutaway
doors, separate flowing front wings, running boards, stand-alone headlamps and
the characteristically upright MG radiator with vertical slats. As had been the motif since the 1920s, a centrally
hinged bonnet, an exposed slab-sided fuel tank and a rear-mounted spare wheel
carrier maintained the period-look.
Where modernity's intrusion was unobtrusive, such as the independent front
suspension, it was welcomed but some changes attracted criticism from a
few. The sturdy chromium plated bumper-bars
added weight which it had be MG’s practice to avoid but reflected the needs of
the US market where sales were overwhelmingly in urban areas where owners
shared parking spaces with domestic automobiles increasingly equipped with
substantial bumpers with something of the quality of the battering ram. Also controversial were the smaller diameter,
pressed-steel disc wheels which replaced that sports-car staple, the TC’s tall,
spindly spoked wire-wheels. It was again
the intrusion of the rationalists.
Because different wire-wheels would have had to be made to accommodate
the arms and links of the rack and pinion steering, the corporation refused to authorize the design, tooling and production for a part unique to one, low-volume
model. The disc wheels actually offered
advantages, being much easier to clean and not as prone to the damage and distortion
the wire wheels suffered when used on secondary roads.
The TD was much improved
but there was a price to be paid.
Weighing some 200 lbs (90 KG) more than the TC while enjoying only the
same 54 horsepower, the TD was less lively than its predecessor, something a
change in gearing only partially disguised so for those who wished for more, in 1950 the factory made available a "competition" version with a higher compression ratio which delivered 62 horsepower, a useful increase of more than 10%. Officially, the "competition" TD was sold only in markets where high-octane petrol could be purchased at the pump but dealers entered into arrangements with the factory so those with access to supplies of aviation fuel could enjoy the experience. However, few had bought TCs for their outright performance numbers
and the increasing gulf between the little sports cars and the ever more
powerful vehicles which began to surround them seems not to have been
sufficient to dampen demand, customers flocking to buy TDs upon its debut in
1949 and over its four-year run, some thirty-thousand would be build, most
destined for the US market, sales encouraged somewhat by Sterling in September 1949 being devalued to US$2.80, an adjustment of around a third, correcting the absurd post-war maintenance of the Stg£1=US$4.03 peg set in 1940.
MG TF (1953-1955,
9600 built).
The TF was the last of the square-riggers. It was also an accident of history, the
result of corporate intrigue within the BMC (British Motor Corporation) conglomerate
of which MG was one, small part and, even at the time, it was no secret the TF
was a stop-gap model there to fill the showrooms with something (sort of) new
before the arrival of the much anticipated MGA.
What had happened was the Healey company reached the BMC boardroom
with a proposal for the Healey 100 before MG got there to make the case for the
MGA and the board, thinking the two too similar to be released at the same
time, put the MGA on hold. It was emblematic of the way business would be done at BMC and the many successor corporations; Healey had
pipped MG by several days, history for centuries recording how such luck
influences events. Thus evolved the TF,
a just slightly less-square rigger launched into the age of the Citroën DS and
Porsche 356; even the Triumph TR2 of the time making cutaway doors look less
archaic. The TD obviously couldn’t be
made to look modern and the facelift it gained to bridge the gap between the
square riggers and the sleek MGA was a quick job, essentially grafting the
streamlining techniques of the 1930s to the once upright front, the headlamps
now fared-into the wings, the same expedient Morgan had that same year been
forced to adopt when Lucas advised there would no longer produce the separate
housings; without the demand from MG, the economics of scale to maintain the
product just in the low volume Morgan would absorb, no longer existed. Mechanically, so little-changed was the TF that
it could have be thought the TD Mark II had the appearance not so differed. Visually refined with a sloping radiator
grille that for the first time concealed a separate radiator, the bonnet now
sloped forward, something achieved by lowering the radiator housing by three
and a half inches (90 mm) in relation to the top of the scuttle, the view from the screen that of a Hurricane compared to the Spitfire-like TD. The front wings with the now partially
integrated headlamps were themselves fared into the bonnet sides in
conventional streamlining style while the rear end gained modifications to the
fuel tank and spare wheel mounting which resulted in a neater finish. In a nod to tradition, perhaps to distract
from other changes, the revised facia panel re-gained the octagonal
instrumentation of the pre-war years, a nostalgic touch very well received, as
was the return of the option of wire-wheels.
The TF in 1953 was released using the faithful 1250 cm3 XPAG
engine which dated back to the TB Midget in 1939 and there were many who hoped
for and expected more. Whatever
aerodynamic improvement the streamlining had delivered, the TF was still barely
able to top 80 mph (130 km/h) while the Triumph TR2 tempted many with the lure
of the then rare “ton”: 100 mph (160 km/h).
It was still an appealing drive with fine road-holding and handling but was, by any standards, sluggish.
The factory were well aware of this and discussed exotic solutions such
as aluminum components to improve the power to weight ratio but it didn’t take
much thought to works out the solution was that the Americans had taught: a
bigger engine with more power. In mid
1954, the TF 1500 was released, using a 1466 cm3 (89 cubic inch),
big-bore version of the XPAG, now designated XPEG, power increased to a more
useful 63 horsepower. While it didn’t
permit the TF to match the pace of the TR2 or other competition, almost 90 mph
(145 km/h) was now possible and the XPEG did stimulate demand, almost all the 3,400
TF 1500s shipped to the US.
MGA (1955-1962,
101,181 built)
The TF was the
end of MG’s square-rigger era, the introduction in 1955 of the MGA both long
awaited and much overdue. Neither
mechanically nor stylistically was it ground-breaking and even during its
lifetime would come to be thought old fashioned but at the time of release the sensuous,
flowing lines were much admired and in the decades since, appreciation has
increased, the MGA today a desirable classic.
It was powered by a 1489 cm3 (91 cubic inch) version of the
corporate 'B' series engine and as a design exercise had actually been finalized some two years before it was introduced and slated to replace the TD but
corporate politics prevailed. By 1955,
it had been intended to announce the MGA and use three pre-release cars (code-named
EX 182) to contest the Le Mans 24 hour race in June. That was thwarted by delays in the supply of
parts so the three were forced to compete as prototypes rather than in the
production class for which they'd been prepared. Against the more formidable competition of pure race cars, success was
unlikely but reliability was proved, one finishing an outright twelfth and the
team finished a creditable fifth and sixth in their class although everything
was overshadowed by the horrific crash that year which killed eighty-four, one
of the MGs involved in the aftermath of the disaster. Encouraged, three were entered in September’s
RAC Tourist Trophy in Ulster, the fifth round of the FIA World Sports Car
Championship, two with experimental double overhead camshaft (DOHC) engines, a
configuration which later and unhappily would figure in MGA history.
First shown at the 1955 Frankfurt Motor Show, the MGA 1500 was
an immediate success; some 60,000 built between 1955-1959, the great bulk of
which were exported, the US again the most popular destination. In 1956, the roadster was augmented by a
fixed head coupé (FHC) which, in a sign of the times, included many of the refinements
saloon buyers had come to expect including wind-up windows and lockable door
handles which, while appreciated luxuries, did make the FHC about 100 lb (45
KG) heavier so acceleration suffered a little but, such were the vagaries of
aerodynamics that top speed increased a little, a well tuned FHC able to attain
the magic ton which just eluded the roadster, the owners of which turned to the
multitude of tuners if they wanted more.
Having earlier boosted the 1500 from 68 to 72 horsepower, the
factory in 1959 again gave owners more, the engine enlarged to 1588 cm3
(97 cubic inch), the new model named MGA 1600, the additional 6 horsepower and
the more relevant 17% increase in torque meaning the “ton” was now topped by
all models and there was a dramatic improvement in braking, vastly superior
(and really overdue) discs fitted at front.
Revisions to the suspension were part of normal product development but
what was much appreciated on the roadster were the Perspex siding side windows which
now sound primitive but were quite an improvement on the celluloid flaps used
on the 1500. In 1961, for the MGA’s
swansong, capacity was again enlarged, this time to 1622 cm3 (99
cubic inch), additional internal changes boosting power to 90 horsepower, top
speed now a heady 106 mph (170 km/h). To
mark the change, the factory designated the 1622-equipped cars the MGA Mark II,
production of which totaled 8,198 roadsters and 521 FHCs.
MGA
Twin Cam (1958-1960, 2111 built).
In the English way of things, the most famous and
celebrated of the MGAs is the least successful and the one at the time damned as a failure. The first MG since the OHC PB
in 1936 not to use an OHV engine, the DOHC Twin Cam used an engine not fitted
to any other car and in that sense of uniqueness ranks with the Triumph Stag in
the annals of British engineering failures although MGs problems were at least
(sort of) excusable given the analytical tools of the time and, as ultimately
transpired, easily fixable, unlike Triumph’s unfortunate V8. Although not used in the production MGA Twin
Cam until 1958, the DOHC engine had enjoyed a long development, the basic
design completed in 1954 and two prototype versions were in 1955 fielded for
the RAC Tourist Trophy in Ulster and although not successful, the factory
wasn’t deterred, refining the concept and using them to set world speed records
in various classes in 1956 & 1957. Critically however, most development work was in high-speed competition rather than the conditions under which most motorists operate their cars on public roads. Using the 1588 cm3 block, the DOHC “B” series was in the
classic mold of small 1950s high-performance engines: an aluminum cross-flow
cylinder head with twin overhead camshafts operating valves angled at 80o
in hemispherical combustion chambers with a high compression ratio. Twin 1 ¾ SU carburetors provided the
induction while on the opposing side, an imposing exhaust manifold boasted
separate downpipes for each cylinder.
The impressive specification yielded a healthy 108 bhp @ 6700 rpm and
top speed was rated at 113 mph (180 km/h), testers reporting sparkling
acceleration at all but the lowest speeds.
Cognizant of the pace, the factory fitted disc brakes on all four wheels
and this time, wire wheels weren’t even optional, the required Dunlop Road
Speed tyres suitable only for the ventilated Dunlop centre-lock disc wheels. Radically different though it was under the
skin, there were few visual differences to distinguish the Twin Cam from its
more mundane cousins, an approach Mercedes-Benz would later adopt for its
300SEL 6.3 and 450SEL 6.9 Q-ships. Only
the purposeful wheels, discreet Twin Cam badges and some details changes to the
interior (including a tachometer and speedometer that accommodated the higher
limits) provided the external visual clues.
Like the Stag, the Twin Cam attracted praise upon release and,
like the Stag, the reliability issues soon surfaced. Reports emerged first of excessive oil
consumption which fouled spark plugs and the factory experimented with several
variations of piston rings before settling on the replacement of the top chrome
ring with one of cast iron and a scraper with an expansion ring; these changes resulted
in normal oil consumption. What was not
solved until the Twin Cam had been discontinued was what ruined its reputation
and doomed the engine: the propensity to burn holes in the top of pistons #3 or
#4. Applying conventional wisdom, the
factory first retarded the ignition timing, then, assuming owners were,
contrary to operating instructions, using cheaper, lower octane petrol, lowered
the compression ratio from 9.9:1 to 8.3:1, both changes reducing power in the
quest for reliability, a trade-off well-known to engineers. The sacrifice however failed to solve the
problem and pistons continue to fail.
What baffled the engineers was they were unable to replicate the issue
in their tests, even under sustained and extreme loadings. Their tests however, while imposing demands
beyond what any road car would be subjected to, were performed usually in a
workshop, on a static test-bed. By mid
1959, the factory gave up and the Twin Cam was withdrawn from sale, the
engineers not discovering the cause until 1960 and those findings they chose not
to publicize. Later, amateurs would
trace the problem to resonant vibration which, under conditions encountered
when actually driving (as opposed to what happens under extreme load on a test-bed), at certain
engine speeds, the SU carburetors would suffer foaming of the fuel in the float
chamber which caused the fuel/air mixture to run lean, greatly increasing the
heat in the combustion chamber causing the aluminum pistons to begin to melt. The solution was no more
complex than the insertion of flexible, vibration isolating mounts between the
intake manifold and carburetors. It was
a cheap and simple fix.
In 1960, MGs engineers had reached the same conclusion. After disassembling several engines, they noted the balance of the production units was well below the levels of precision they had specified as a result of testing the prototypes, the production engines exhibiting two periods of natural vibration around 3200 and 5600 rpm. With the stock gearing which most Twin Cams used, 3200 rpm coincided with what were then typical highway cruising speeds. So, they returned to the test bed and, instead of pushing the engines beyond their limit, instead ran them to the point of vibration and found the float on the rear carburetor would hang on its spindle and not drop, inducing a lean mixture which burned holes in either #3 or #4 piston. In minutes they improvised a flexible mounting using nothing more exotic than some thin sheet-rubber but the solution came too late, the discontinued Twin Cam’s reputation too sullied for a revival. A decade on, much the same tale would be told of Norton’s 750 Combat.
So only 2,111 Twin Cams were sold, 1,801 of which were roadsters. Making the best of a bad situation, the factory used the residual stockpile of Twin Cam bits and pieces (other than the engine) and created some up-graded models often referred to as the “De Luxe” which, although MG never formerly applied the designation, shameless dealers advertised them as the “Deluxe”, "De Luxe” or De-Luxe”. Production was limited by the availability of parts and only 82 1600s were built, along with 313 of the more desirable Mk II 1622. Except for the Dunlop wheels and four wheel disc brakes, there’s no commonality in the specification, some using a genuine Twin Cam chassis, some with the “hybrid” competition shell and a mix of other options while many were essentially standard MGAs differing only in the wheels and brakes. Because of the rarity and upgraded specification, the “De luxe” models are now second only to the Twin Cam in desirability.
The other MGA: Lindsay Lohan at MGA Entertainment's "Bratz", 2003 Teen Choice Awards, Universal Amphitheatre, Universal City, California.
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