1926 - Present
The Origins Of The SL
Some of the most popular pages on this
site are dedicated to the wonderful Mercedes SL - so
lets take a look at its origins, development and heritage.
If you go back far enough, then strictly speaking the
first of the line was a Mercedes, without the 'Benz'.
The "28/95" model was announced in 1921, prior to the
merger with Benz in 1926. It was fitted with a 725Occ
six-cylinder engine and, unusually for the period, four-wheel
Early versions were not supercharged, but a
'blower' was later added, and Max Sailer used one of
these cars to finish second in the Targa Florio
The Influence of Dr. Ferdinand Porsche
But it was the 33/180, or "K" model, that would establish
Mercedes-Benz as a manufacturer of highly polished sports
cars. Designed by a then little known Dr. Ferdinand
Porsche, who was Mercedes technical director at the
time, it featured a 6.2-litre six-cylinder engine with
a single overhead cam valve gear layout, and was equipped
with a supercharger.
The interesting thing about the use of the supercharger
was that it was not permanently engaged, but rather
brought into use by a mechanical linkage when the driver
fully depressed the accelerator.
Bentley, Mercedes main
rival on the race track, was to quickly learn that this
use of the supercharger "only when needed" gave the
car a huge reliability advantage - that naturally translated
into race success!
This supercharger also differed from most other layouts
in that it pumped air into the carburettor while on
its way to the engine (rather than extracting the air/fuel
mixture from the carburettor) and hence impelling it
into the engine.
This worked well enough at high engine
speeds, but at low engine rpm it consumed a great deal
At the time the "K" model was claimed to be the first-ever
standard road car to have a 100mph top speed, and while
it was a very impressive car to look at, it suffered
from having the most appalling brakes
In 1927 an improved version of the 'K' was introduced,
the 36/220 or "S" model. It had a larger, 6.8 litre
engine which developed 120bhp at 3000rpm, and that was
without engaging the supercharger.
When the driver did engage the supercharger
the power would shoot up to a whopping 180bhp, giving
the "S" a top speed of around 110mph. But even more
importantly than the increase in power and speed, the
"S" had much improved handling, due greatly to its lower
centre of gravity.
Naturally the brakes
were also upgraded
- and a total of 146 of the "S" were manufactured. To
prove the point, Rudolph Caracciola and Otto Merz drove
'works' racing examples, the latter winning the German
GP of 1927, with other Mercedes-Benz models in second
an third places.
Who would have guessed the
Benz Viktoria would lead to such wonderful classics
as the Mercedes SL and SLC's.
The SSKL with chassis drill
holes, the engineers would find any way to make
Good for 225bhp, but only
33 would be built.
The overhead valve straight
eight engine of the 540K, while perfectly suited
to autobahn conditions, did not favour the Nurburgring.
Compare the two images above,
and notice what a huge difference both colour
and white-wall tyres make to the sporting pretensions
of the 540K.
The 300SL "Gullwing",
a purists dream.
The quintessential object
The 300SL Roadster allowed
women a more dignified way of entering and exiting
Unlike the Jaguar D-Type,
the Mercedes 300SLR relied on drum brakes. And,
of course, the revolutionary 'Air Wing'.
The 190SL marked Mercedes
entry into the competitive sports car market,
till then dominated by the likes of Austin Healey
The pretty 230SL, affectionately
known as the 'Pagoda' due to its inverted hard
The R107 350SL quickly won
the respect of mechanics over the world with
its durability and reliability, earning it the
title 'Der Panzerwagen'.
The R107 would re-introduce
the stylish coupe with the 350SLC, this time
as a 2+2.
The Mercedes C111, the supercar
that never was.
The SS and SSK
The "SS" arrived in 1928, this being a lighter version
of the "S" (and thus starts the tie in with "SL"). The
engine was further enlarged to 7020cc, however this
model was soon followed by arguably the most famous
of the early Mercedes sports cars, the "SSK".
the wheelbase was shortened, a larger engine was installed
which was good for 170bhp (unblown) and an enormous
225bhp with supercharger engaged. While there would
be only 112 "SS" built, it was surely a tragedy that
a paltry 33 "SSK" models were built.
Both were successful competition cars in Works' drivers'
hands. Caracciola won the British Tourist Trophy race
of 1929, averaging a whopping 78.26mph (remember this
was 1929!) in rainy conditions, although many would
claim it was because of the wet conditions and the resultant
reduction in tyre
wear that helped Caracciola to victory.
He soon silenced his critics, by taking his SSK to victory
in the Irish and German Grands Prix of 1930 and 1931
The ultimate development of this family was the "SM"
model of 1931, of which only five examples were ever
made, and these were for the company's own use! The"SM"
used the same engine as the "SSK", but had a larger
We cannot confirm or deny the following,
but it has been reported that, with supercharger engaged,
the "SM" would make a Trumpeting Elephant
But whatever it sounded like, it must have sent a tingle
down the spine of the driver when he had a whopping
300bhp on tap.
Never ones to rely on engine capacity alone, Mercedes
engineers copiously drilled holes through the chassis
to reduce weight, and they were successful, as the car
weighed in at only 2700lb, way less than the competition.
It was, in every way, a fearsome machine, having a top
speed of 147mph (in ideal conditions), and one fitted
with a purpose built streamlined body actually clocked
156mph. Caracciola would soon rack up another victory,
taking out the 1931 Mille Miglia
single handed, and
later the German Grand Prix
(putting to shame a couple
of Type 51 Bugattis).
Mercedes Enters Grand Prix Racing
It was only natural therefore that parent company Daimler
Benz would soon want to "officially" enter Grand Prix
racing, and would turn their attention away from the
"guts and glory" road monsters and develop smaller,
lighter and better handling
racing cars. For the 1930s,
they developed a very different type of road car which
upheld the company's sporting image.
The "500K" was a 5 litre supercharged grand tourer,
introduced in 1933, beautifully made and finished, but
with rather disappointing performance. It was softly
sprung, and more suited to the Corniche than the Nurburgring
Its overhead valve straight eight-cylinder engine developed
110bhp (unblown) and 160bhp with the supercharger engaged.
The "500K"s replacement came in 1936 with the 540K,
effectively the same chassis, and with a similar appearance
and choice of bodies, but a 5.4 litre version of the
engine with 115bhp (unblown) or 180bhp with supercharger
engaged. Even so, this car had a maximum speed of only
Unfortunately the second world war would virtually
destroy the Daimler-Benz company, and it would not be
until 1952 that they were able to showcase their new
And what a car it was, featuring a sleek body style,
with a coupe roof and lift-up gull-wing doors, all built
upon a chassis made from a mass of small diameter tubes,
dubbed the "space frame".
The engine fitted to the first prototype
was good for 175bhp, and was a development
of the new 3 litre saloon unit, but canted well over
to one side to allow a low bonnet line.
In June, Hermann
and Lang would drive the car to victory in the Le Mans
24 Hour race, at a record 96.67mph average, and this
was just one of many wins during the season.
Enter The Legendary 300SL
However, it was not until the spring of 1954 that the 300SL
production car was announced, with modified styling
and a more passenger friendly trimmed interior. The
engine had been further developed, now enhanced with
direct fuel injection
and producing 215bhp from its
2996cc capacity, giving the car a top speed of around
It was a formidable car, perhaps only let down
by the high-pivot swing axle rear suspension, which
could produce vicious oversteer in hard cornering conditions.
This suspension set up would remain a contentious issue
through later model SL's (even though it would undergo
numerous revisions) until being phased out with the
introduction of the "350SL" in 1971.
The coupe gave way to an open roadster (300SL Roadster
) from 1957, with
conventional front-hinged doors, and an optional hardtop
was available. More important still, this derivative
had a much more effective low-pivot swing axle rear
And by the time production ended
in 1963 some 3250 cars had been built.
The More Affordable 190SL
But these two
cars were extremely expensive, and Mercedes needed to
create a more affordable sports car to compete with
the likes of the Austin Healey
and Jaguar E-Type
answer came in 1955 with the release of the "190SL
It may have lacked some of the glamour of the larger
car (being based on the floor-pan, engine and suspension
of the 180 saloon), but retained Mercedes key values
of roadholding, quality and desirability.
The 4 cylinder
engine may not have kept up with the competition, but
not many seemed to mind when, all things considered,
the reliability and allure of the three pointed star
sat up front.
It was during the reign of the 190SL that Mercedes developed
perhaps their most ferocious racing sports car, used
in only the 1955 season, the legendary 300SLR. This
was based on the general layout of the then-dominant
W 196 Formula, however changes were made to the space
frame chassis to allow two seats and an all-enveloping
body style. Its 3 litre straight-eight engine had desmodromic
(positive opening and closing) valve gear, and produced
300bhp, giving the car a top speed of 180mph.
Perhaps its only real weakness was that drum brakes
were used, at a time when Jaguar's D-Type was revolutionizing
motor racing with disc brakes. To provide extra braking
capacity, the Mercedes engineers developed a massive
hinge-up air brake across the tail, behind the cockpit,
which was not only effective from high-speeds, but when
in operation it put considerable down force on the rear
tires, in the process increasing the overall cornering
power. A total of ten cars were built, of which two
(that remained un-raced) were almost 300SL 'Gullwing'
look-alikes. In one season, the team cars entered six
events, winning five!
Tragedy Strikes At Le Mans
Things could not have looked brighter for Mercedes,
but tragedy was just around the corner at Le Mans
. The crash and ensuing fire
killed the SLR’s driver and over 80 of the
spectators. Mercedes-Benz immediately withdrew the remainder
of its team – including the Moss/Fangio SLR –
and the Hawthorn/Bueb team would go on to register a
rather hollow victory.
The fact that Hawthorn had set a new lap record of
122.39 mph prior to the accident was quickly forgotten,
and many believed the Jaguars superior disc-brake setup
would have allowed the “D” to catch and
perhaps pass the “air-brake” SLR, but that
was only speculation. Amazingly the Austin-Healey involved was driven by Lance Macklin, who survived, and the car stayed on the track only moderately damaged. The Healey did no damage to any other car or person and Lance walked away.
and Ivor Bueb, who were piloting
the Jag, went on to a rather hollow victory - while
it would take until 1988 for Mercedes to return to competitive
racing, when they would join forces with the Swiss Sauber
team in the Sports Prototype Championship, then lining
up on the grid with its partner AMG in the German Touring
Car Championship (DTM).
The Beautiful Pagoda's
But lets get back to the SL's! It would be in 1963 that
both the 190SL
would be replaced by a single
car - the 230SL
. The layout and philosophy was much
similar to that of a small car, and it used a conventional
pressed steel body/chassis hull, and suspension and
engine components lifted from the latest 220SE
The engine, at first, was a 170hp/2306cc overhead-cam
six-cylinder unit, with indirect fuel injection
was almost a work of art), there was power-steering
(unusual for this period), and the existing low-pivot
rear suspension was carried over.
To many people, this
model is best remembered by the unusual 'pagoda' style
of its optional hardtop, although interestingly there
was some sales resistance to this feature when it was
However the car's image was instantly improved when
the 'works' rally driver Eugen Bohringer took one on
the Liege-Sofia-Liege marathon rally of 1963, and won
it outright. Two developments of this car were produced
- the 250SL
, built in 1967, and the 280SL
(with a 2778cc
engine) produced from 1968 to the end of production
The Incredibly Popular R107 Panzerwagens
Then came arguably the most popular SL of all, the R107 350SL
. Much larger and 'softer', brimming with creature
comforts and still directed at the same luxury-conscious
The monocoque construction used drive lines
and suspension from the current saloon models, notably
the still unreleased 1972 S-Class. The 3.5 litre V8
engine was a beautiful device, producing 220bhp at 5800rpm
and giving the autobahn cruiser an effortless top speed
But the new SL was far from being 'Super Light', weighing
4000lb and requiring massive 4 wheel disc brakes. A
4.5 litre V8 engine was soon optional (standard in the
US), the extra size being required to help maintain
the cars performance in light of the additional anti-pollution gear being incorporated during the environmentally
conscious 1970's. And, for the first time ever, a long-wheel
2+2-seater fixed-head coupe would be available - the 350SLC
By the end of the 1970s, the latest light-alloy 3.8
and 5.0 litre versions of the V8 engines were fitted,
and production would continue until 1989, a run of 18
years! While the previous model SL was nick-named the
'Pagoda', the R107 would be dubbed 'Der Panzerwagen'
due to its reliability, strength and longevity (some
examples covering over a million miles without the removal
of the heads!)
But Mercedes decided to once again dabble
in the 'super car' genre, developing a ultra-high-performance
prototype, the Wankel rotary engined C111.
This state-of-the-art mid-engined two-seater coupe used
fully independent suspension, while the 3 Rotor 3600cc
engine was good for 280bhp and a top speed of around
The breathtaking performance was not the result
of the engine alone, the sleek fibreglass body having
a low drag co-efficient and sitting extremely low to
the ground. Within a year Mercedes had developed a second
evolution, this time using a 4 rotor engine with a 4800cc
capacity and good for 350bhp and 190mph. Ultimately
however the cost and ongoing reliability issues would
force Mercedes to shelve the project, the C111 joining
the BMW M1 as the stuff of legends.
Also see: Mercedes History
| Mercedes SL's By Model
| The Daimler-Benz Story - Built To A Standard Few Could Hope To Achieve (USA Site)