liter inline 8
lb-ft @ 1500 rpm (original)
hp @ 2800 rpm (original)
hp per liter
DaimlerChrysler Press Release) When
the Mercedes-Benz Type 770 was presented at the Paris Automobile
Show in the autumn of 1930, this “Grand Mercedes” far outstripped
the familiar dimensions in the category of high-quality,
high-performance luxury automobiles. Right off the bat, it set a new
standard in the world of top-flight passenger cars for prospective
customers, the public and the experts. Internally designated W 07,
the car indeed was the largest and, in every respect, most luxurious
Mercedes offered by Daimler-Benz to its customers, costing the price
of a single-family home, but in return featuring an ultramodern 200
hp supercharged engine and a “Sindelfingen body” with sensational
appointments and an exquisite finish.
7.7-liter in-line eight-cylinder
with fine ingredients
The engine offered a
number of exceptional features to a technically extremely
well-versed clientele. The cylinder block of the voluminous
(displacement 7655 cm3) in-line eight-cylinder engine, made of
extremely wear-resistant chrome-nickel-alloyed gray cast iron, was
combined with a heavily ribbed crankcase bottom half incorporating
an integral oil pan made of electron metal. Carefully balanced
statically and dynamically, the chrome-nickel steel crankshaft with
solid-forged counterweights ran in nine main bearings and
additionally had a progressively acting vibration damper at its
front end to ensure even smoother and quieter running of the power
plant, internally called the M 07.
It went without saying
that such an engine could not have a simple side-valve
configuration. The overhead valves in the gray iron cylinder head
were actuated by means of roller tappets, push rods and rocker arms
controlled by a side camshaft running in nine bearings.
carburetor, accelerator pump and cold-starting aid were the most
important components of the energy supply system, supported by a
light-alloy inlet manifold automatically heated by exhaust gas and
thermostat controlled hot-air flaps. The ignition system also
evidenced technical finesse. The combined battery-magneto ignition,
whose two elements operated independent of each other, ensured
reliable double ignition of the sparkplug sets recessed in the
cylinder head on the left and right sides.
Power to spare with the
(4.7:1) long-stroke engine developed 150 hp at a moderate 2800
revolutions; the high torque of 40 mkg was already available at 1200
rpm. That was easily enough to satisfy prestige requirements and
attain a top speed of 150 km/h. But it was still too little for a
Accordingly, a supercharger – for the price of a respectable
intermediate class car – was an available option. But the Roots
blower as high-pitched power booster in Mercedes sports cars was
quite out of place in a luxury car. Owing to very effective intake
noise damping, it mutated into a “whisperer” in the 770 with now
only a muted snorting sound.
For better heat
dissipation – and as status symbol – the supercharger-equipped
models were fitted with exhaust pipes sheathed in flexible metal
hose projecting from the right-hand side of the hood. In the end,
only a few customers actually bought the car without a supercharger.
With the aid of the
supercharger, engine output rose to 200 hp at the same engine speed,
torque increased to a dizzying 54.6 mkg at 1500 rpm, and the top
speed to 160 kilometers per hour. That provided the kick that earned
the Grand Mercedes the nickname “Road Express”.
Ride comfort and safety
Ball gear shift and
helical spur gears were the special features of the three-speed
gearbox installed in a light-alloy housing. It was complemented by
an overdrive box to reduce engine speed at higher traveling speeds;
this could be engaged in any gear, in effect giving the car six
Power was transferred by
a dry double-plate clutch to the pressed sheet-steel rigid banjo
rear axle with cast differential case made of light alloy. The
forged H-beam solid-end front axle made of chrome-nickel steel
likewise was rigid. Both axles were attached by semi-elliptic
springs to the semi-drop-frame, a pressed U-shaped sheet-steel
lever-type dampers reduced road shock, and anti-shimmy blocks on the
front spring shackles suppressed wheel wobble. A fully automatic
central lubrication system supplied all lubrication points of the
chassis, including the Cardan universal joint, with motor oil heated
to operating temperature.
The helical spindle
steering was said to have outstanding road feel, but was not exactly
light. The car was equipped either with wood or wire spoke wheels as
requested by the customer.
The high demands on
operating convenience and safety were met by the mechanically
actuated, generously dimensioned brakes, whose huge drums had
longitudinal ribs for cooling and the actuation of which was
facilitated by a vacuum servo unit. They decelerated the 2.7 ton car
In the interaction of its parts, the entire chassis design gave the
Grand Mercedes an unusual ride comfort and a very high level of
handling safety for a car of that period.
The “Sindelfingen body”
Upon the introduction of
the 770, the bodies built in Sindelfingen already had gained a
certain amount of fame, as several of the Mercedes-Benz models, for
instance the “Nürburg” type, had been delivered for some time “ex
works Sindelfingen” complete with coachwork and ready-to-drive.
What was new, however,
was that a car of the top luxury class now also could be delivered
complete – in keeping with the spirit of the times, in the versions
Pullman sedan, six-seater (open) touring car, four-door Cabriolet D
and six-seater Cabriolet F, which all underscored the desired
prestigious character of the Grand Mercedes. The Cabriolets B (four
windows) and C (two windows), on the other hand, gave the long, low
chassis of the 770 a more sporty touch.
The flawless workmanship
of the bodies and their interior met with enthusiastic approval on
account of the choice taste and excellently quality they embodied.
The reputation of the “Sindelfingen body” and its agile creators was
broadcast throughout the world.
As a matter of
principle, the buyer of the 770 could influence the final execution,
both of the exterior and the interior, to suit his taste. So it is
not surprising that, to a large extent, each car bore the personal
signature of its original owner.
Exterior with flowing lines
Characteristic of the
Grand Mercedes was its face, with the vertical, slightly wedged
chrome-plated honeycomb radiator, usually protected by a
stone-deflecting herringbone-pattern grille set before it. Alongside
the radiator, huge headlamps set on bows – an arrangement which can
still be termed “classic” – threw far-reaching headlamp beams.
The imposing hood went
over into coachwork which emphasized length with a comparatively low
belt line; with the wheelbase of 3750 mm, in every version it
afforded the occupants plenty of room, particularly considering that
the width of 1840 mm was not stingy either.
The double bumpers made
of spring steel had thick layers of rubber and effectively protected
the 5600 mm long car against minor impact. The spare wheels were
stored in recesses in the front fenders.
Even a reversing light was
In the course of two
updates to the bodies in 1934 and 1936, the hood received horizontal
ventilation slots to add still more emphasis to the long, flowing
lines, and the fenders, too, were more strongly cambered and got
softer lines, side aprons and harmonious transitions to the running
boards. The tank filler pipe disappeared behind a flap in the rear
fender. The bow for the lamp also was discarded, so that the
monumental and unchanged vertical radiator plowed through the air
even more impressively.
Depending on body type and customer wishes, the rear end featured a
luggage deck with box or even a proper trunk with elegant,
individually handmade cases.
Interior with consummate luxury
The opulent technical
appointments “under the skin” had their counterpart in the
instruments of the centrally arranged dashboard set in polished
wood: speedometer with tops of 160 km/h, including trip and overall
mileage recorder; rev counter, clock, remote cooling water
thermometer, oil pressure gauge, fuel gauge and a combined ammeter
and voltmeter. The horn was operated by the signal ring on the
steering wheel, the hub of which conveniently incorporated the
levers for mixture regulation, ignition timing and overdrive
The “air conditioning”
was typical of those days. It was the hinged windshield, vertical in
the first versions, but cautiously retouched in the years following,
becoming increasingly raked, to achieve a more appealing streamline.
Almost as numerous as
the number of cars built were the seating and upholstery versions:
leather, velvet, but also exotic materials; colors to suit the
customer. Ample polished wood applications, integral ashtrays,
oddments boxes, built-in bar, driver intercom served for comfort,
convenience, and as a feast for the eyes. And let’s not forget the
powerful Autosuper radio with two loudspeakers each at the front and
rear, unfortunately without stereo effect. A forced-air heater made
for cozy warmth in the rear passenger compartment and additionally
supported the electric windshield heater.
Individual luxury in the
770 was understood and gave it that special flair which the rich and
powerful of all shades treasure, for which reason they were all too
happy to make use of the Grand Mercedes. Daimler-Benz manufactured
119 units of the W 07 between September 1930 and June 1938: 42
Pullman sedans, 26 open touring cars, 18 Cabriolet D, 14 Cabriolet
B, C and F and 19 chassis. The successor was already knocking on the
Avant-garde design in the
In February 1938, at the
IAMA International Motor Show in Berlin, the evolutionary stage of
the Grand Mercedes was launched, internally designated W 150.
Largely redesigned, the car, which continued to be called the
Mercedes-Benz 770, manifested the art of automobile manufacture in
perfection, the creativity of its engineers, and the inimitable
avantgarde design work of Daimler-Benz.
Power plant and drive train in
The power plant was
unchanged as regards fundamental dimensions, but featured a number
of modifications, as documented by the new engine code M 150.
The crankcase was now
completely made of light alloy, the exhaust valves were
sodium-cooled, ignition control was automatic, and the water pump
was rigidly driven by the oil pump shaft. Three geared oil pumps
quite effectively ensured forced-feed lubrication.
Even the engine was
exquisitely finished. Cylinder block and accessories housings were
enameled black; brass lines and the fan were chrome-plated;
light-alloy elements featured a polished hammertone finish.
The supercharger, now
standard, featured higher efficiency and was engaged with the
accelerator pedal, as usual. In naturally aspirated mode, the
engine, with a compression ratio of 6.1:1, now developed 155 hp,
with supercharger 230 hp. Torque rose to 47 mkg at 1900 rpm and 56
mkg at 2000 rpm, respectively. The top speed was 170 km/h.The
all-synchromesh four-speed gearbox was complemented by a remote
gear, installed in the differential case, which could be
additionally engaged at any speed. Inconvenient to use and
unnecessary to boost performance, this configuration was replaced in
1939 by a five-speed gearbox whose fifth gear functioned as an
overdrive. Power transfer was effected by a stronger single-plate
For special purposes,
there was an engine with a compression ratio of 7.2:1, two
double-barrel updraft carburetors and two superchargers. The power
output: 160 hp in naturally aspirated mode, 400 hp with both
superchargers engaged, in each case at 3600 rpm. Top speed ranged
from 180 to 200 km/h.
However, only five cars
with this variant were ever built.
Oval-tube frame, individual wheel
suspension and hydraulic brakes
Entirely new were the
frame and axles; the brakes had even better grip. The chassis side
members, made of oval tube, were joined with six cylindrical cross
members to make a very torsion-resistant ladder-type frame.
The now individually
coil-sprung front wheels were located by A-frame arms arranged in a
parallelogram. But the real surprise was the rear axle, a
“double-joint axle”, as the trade literature termed it, designed
according to the De Dion principle. Daimler-Benz themselves termed
it a “laterally stable parallel-wheel axle.” It had constant camber
and track and was complemented by a V-shaped anti-sway linkage
connected by a rubber doughnut to the middle cross tube. To the next
but last cross member, the three-point rubber-mounted differential
was attached. Naturally, the rear axle also had coil springs; from
1939 on double coil springs, one inside the other.
The already highly
effective brakes of the first 770 were adapted to the successor’s
increased performance and up to 900 kilograms of additional weight;
they were now hydraulically operated and continued to have vacuum
servo assistance. Each wheel had two brake cylinders, each serving
one of the self-adjusting primary brake shoes. The new sheet-steel
disc wheels had center mounts.
Larger dimensions, lower overall
The evolutionary 770 was
stretched another 40 centimeters to six meters in length; its
wheelbase was a proud 3880 mm, and the width, too, grew by 23 cm to
a respectable 2.07 m. Following the fashion, the overall height was
reduced by three centimeters: Hats and caps were not as tall as top
hats. The wedge-shaped radiator was now slightly sloped. The
standard bodies offered were the Pullman sedan with saloon
partition, the open touring car, the Cabriolets D and F. Special
wishes continued to be catered to, and all variants also could be
supplied in armored versions. In that case the production code was
then W 150 II, and the car weighed no less than 4800 kilograms;
speed was limited to 80 km/h because of the bulletproof cell-type
A total of 88 W 150’s
rolled out of the Sindelfingen factory bay by mid 1943. They saw
service partly up to the late 1960’s, and a number of specimens are
still preserved today in museums and private collections.
The Grand Mercedes,
especially in the king-size format of the evolution stage, pointed
the way with its avant-garde engineering and, to this day,
determines the form, safety, comfort, performance and elegance of
particularly prestigious limousines. In its day it contributed
decisively to further enhance the image of the Mercedes-Benz make
all over the world.