ICONS FOR CONNOISSEURS - THIRTY YEARS OF THE BMW M1
Source: BMW Group In America
Mar 29, 2008 - 8:31:59 AM
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Munich. The star came in pure white: When the 64th Paris Motor Show opened its
gates in autumn 1978, sports car fans and lovers had only one destination - the
stand of BMW Motorsport GmbH. There they were able to admire a super-low,
dynamic new model which made it clear at very first sight that this was
Germany's fastest road-going sports car: the BMW M1, 1,140 millimeters (44.9" )
high, 204 kW (277 bhp) strong, and well over 260 km/h (160 mph) fast. "Everybody
was crowding around BMW's new mid-engined sports car", wrote the press. And:
"The list of orders coming in exceeds even the wildest expectations - an
American fan of BMW, just to mention one example, has already put in an order
for three M1s."
That was quite something, considering that BMW’s
super-sports car had a price-tag back then in 1978 of exactly DM 100,000, enough
for four BMW 323is plus a couple of optional extras. It is fair to say that few
cars have ever been expected with such excitement and anticipation as the BMW M1
which represented all of BMW’s know-how in motor racing. Project E 26, as the
then still nameless M1 was initially called within the Company, had started in
1976. This was to be the first really unique car built by BMW Motorsport GmbH,
BMW’s motor racing subsidiary established in 1972. The racing company, having
already made a great name for itself in the international racing scene with the
fast BMW 2002 and the highly successful BMW 3.0 CSI, now planned to lift this
success to an even higher level with a competition car specially built and
prepared for the Group four and five racing series.
According to Group
four regulations at the time, qualification required a production run of at
least 400 units in 24 successive months, it had to have two seats and bear a
distinct resemblance from outside with its production counterpart. That made it
quite clear that the E26 had to be not only a thoroughbred racing car, but also
a street-legal sports car.
A Bavarian with Italian blood.
The problem
was that BMW Motorsport GmbH totally lacked the capacity to develop and build
such a car all by itself. After all, this team of specialists had concentrated
on turning series-production cars into racing cars, making the chassis and
suspension tauter and the engine more powerful.
In its lines and design, the
new coupe was intended to clearly boast that special Italian style. It was
modelled around the gull-wing turbo, a turbocharged concept car created in 1972
by BMW designer Paul Bracq. Proceeding from this design study with its rounder
lines, Giorgio Giugiaro created the sharp profile of the M1 with its distinct,
almost jagged edges and corners. Bracq and Giugiaro had already cooperated in
the past in creating the BMW 6 Series coupe.
First choice in the engine
department: a inline-six engine.
Choosing the engine, BMW Motorsport GmbH
initially focused on two concepts: Advance studies of Formula engines had led to
a ten-cylinder code-named the M81, a V-engine with its cylinders at an angle of
144°. Suitably modified, this engine was also examined for its possible use in a
sports car. But then the team around BMW’s Motorsport Director Jochen Neerpasch
quickly opted in favor of a new inline-six, an engine concept supported by the
excellent experience BMW had gained in the CSI races.
After all kinds of
rumours with the grapevine running wild, BMW unveiled the secret in spring 1977,
officially confirming the development of the new super-sports car. Then, in
autumn of the same year, BMW published the first photos of the M1 in production
trim. The car then made its first public appearance half a year later: Together
with TV presenter Dieter Kürten, Jochen Neerpasch proudly introduced the Group
four version in the colors of Motorsport GmbH in a prime-time Saturday evening
sports program on Channel Two of German Television. Although this racing machine
bearing number eleven was not yet ready to go, the first test drives were
scheduled for April 1978.
277 bhp in a purebred sports car.
The big
day finally came in autumn of the same year. The public was able to admire the
first E26 at the Paris Motor Show. By that time the car bore the model
designation M1 standing for the first car developed and built by BMW Motorsport
GmbH.
Measuring 4,360 millimeters (171.7´´ ) in length, 1,824 millimeters
(71.8´´ ) in width and 1,140 millimeters (44.9´´ ) in “height”, the M1 exuded a
genuine flair for power. This mid-engined sports car was driven by a 3.5-liter
inline-six fitted lengthwise in front of the rear axle and developing maximum
output of 277 bhp. Code-named the M88, this engine was based on the
volume-production six-cylinder combined with the four-valve cylinder head
carried over from BMW’s CSI racing engines. Within this two-piece cylinder head,
the lower section formed the combustion and coolant chamber, the upper half
comprised the camshaft bearings and cup tappets.
The fuel/air mixture was
delivered through three double throttle butterfly manifolds featuring six
46-millimeter individual throttle butterflies to the cylinders through two
intake ducts per cylinder measuring 26 millimetres (1.02´´ ) in diameter. The
all-electronic digital ignition system also reflected the latest state of the
art.
Dry sump lubrication bore clear testimony to the sporting genes of
the M1, the car being able to achieve a very high level of lateral acceleration.
Fuel was supplied to the engine from two tanks right and left in front of the
rear axle, each with a capacity of 58 liters (12.8 Imp gals). From the engine
power was transmitted through a ZF five-speed gearbox connected to the engine by
a two-plate dry clutch. The final drive differential came as standard with 40
percent locking action.
264.7 km/h (164.1 mph): Germany’s fastest sports
car.
The six-cylinder engine was smooth and free of vibrations throughout its
entire range of engine speed, even remaining quite docile at lower speeds. This
changed instantaneously once the rev counter hit 5,000 rpm. From there the M88
pushed the M1 forwards up to its top engine speed of 7,000 rpm with gusto making
even the most jaded car testers wax lyrical: “Once the throttle butterflies are
fully open you feel a tremendous kick from behind continuing well beyond the 200
km/h-mark. There is no need to shift to fifth gear, for example, until you reach
a speed of 213 km/h (132 mph) and from there you continue to accelerate up and
up to the car’s top speed.” Which, as recorded by Germany’s leading car magazine
in autumn 1979, was 264.7 km/h (164.1 mph). Acceleration from 0–100 km/h in 5.6
seconds also looked very good, which is not surprising considering the
power-to-weight ratio of 4.7 kg/hp, making things relatively easy for the 204 kW
(277 bhp) engine.
The M1 was conceived and built for racing right from
the start. The elaborate suspension with double wishbones on each wheel,
gas-pressure dampers and two anti-roll bars remain in command throughout the
car’s entire speed range. With the exception of the more comfort-oriented
response of the moving parts and the modified spring/damper setting, the road
suspension was identical to the chassis and suspension on the Group four racing
version. Four inner-vented brake discs ensured phenomenal stopping power from
any speed and the front axle came with 30 percent anti-dive minimising body
movement even when applying the brakes all-out. Tires measuring 205/50 VR 16 at
the front and 225/50 VR 16 at the rear were certainly very big and muscular in
those days.
A low center of gravity of just 460 millimeters (18.5´´ ) above
the road, track measuring 1,550 mm (61.02´´ ) at the front and 1,576 mm (62.04´´
) at the rear, together with the mid-engined concept providing weight
distribution of 44.1/55.9, made the M1 a genuine performer in bends, even though
the car called for an experienced driver when pushed to the limit. Typical of a
mid-engined performance car with a low level of inertia around its vertical
axis, the M1 required quick and forceful counter steering as soon as lateral
acceleration exceeded a reasonable limit and the rear threatened to break away.
But the rack-and-pinion steering without power assistance and with a direct
transmission ratio was perfect for this kind of control. Displaced castor and a
small steering roll radius served at the same time to combine ease of control
with supreme road contact absolutely essential for the active driver. The
twin-joint safety steering column, in turn, was adjustable for reach.
A
racing car with crash-proven passive safety.
Although the M1 was a sports car
par excellence, both the driver and passenger enjoyed a certain standard of
comfort. Though the suspension was firm and taut, it nevertheless absorbed bumps
on the road without requiring the occupants to take any heavy jolts. Indeed, the
driver and passenger were safely cocooned in a rectangular steel-profile
space-frame complete with a bonded and riveted plastic skin free of distortion.
The luggage compartment beneath the front lid was sufficient for a weekend for
two, and even air conditioning was available. And the BMW M1 was safe: Since the
new sports car received general homologation for the entire production series
(as opposed to individual approval of each single model one-by-one), BMW was
required to substantiate the passive safety of the M1 in a series of crash tests
– a precaution which later benefitted many a racing driver.
While the
public was admiring the new super-sports car from Munich, with orders coming in
one after the other, production of the M1 suffered a nasty setback: Lamborghini
was unable to assemble the new car as planned and the order instead had to go to
Baur, the coach-building specialist in Stuttgart. This made the M1 a genuine
challenge in the production process with the space-frame built by Marchesi, the
glass-fibre-reinforced plastic body shell by T.I.R., both in the Italian town of
Modena, and Giorgio Giugiaro’s company ItalDesign assembling these two basic
units and adding the interior trim and equipment. From there the car went to
Stuttgart, where Baur fitted all the mechanical systems and components.
A
big attraction in Formula 1: the Procar Series.
Facing these delays and
re-planning requirements, BMW suddenly became hard pressed for time. After all,
400 units of the new car had to be built within 24 months for homologation as a
Group four competition car. And other companies were also pressing forward. So
to get the M1 on to the race track faster, Motorsport GmbH Director Jochen
Neerpasch, teaming up with Bernie Ecclestone and Max Mosley, launched the Procar
Series with races held just before most of the European Formula 1 Grand Prix
events in the 1979/80 season.
The big difference versus the road going car
was the engine of the Procar racing version. The first step for motor racing was
to tune the M88 six-cylinder the classic, conventional way, with new camshafts,
larger valves, forged pistons, optimized flow ducts, slides instead of throttle
butterflies and a modified exhaust system boosting output to 470–490 bhp. With
this kind of power, the Procar version weighing just 1,020 kilos and fitted with
the longest transmission ratio had a top speed of approximately 310 km/h (192
mph). Goodyear racing tyres measuring 10.0/23.5 x 16 at the front and 12.5/25.0
x 16 at the rear, together with a mighty rear wing, served to provide the right
kind of grip on the road. Driving one of these Group four BMW M1s, Marc Surer
lapped the Northern Circuit of Nurburgring in just 7minutes 55.9
seconds.
Built to Group four regulations, the M1 was not only placed at
the disposal of five Formula 1 drivers in each race for the Procar Trophy, but
was also sold straight from the factory as BMW Motorsport GmbH’s first
ready-to-go racing car at a price of DM 150,000. And indeed, some of the most
renowned racing teams quickly took up this offer. Schnitzer and Heidegger raced
their own M1s on the track, just like Osella in Italy and Ron Dennis in Great
Britain.
Putting up a unique show for the crowd:Driving skill was the
decisive factor.
Benefitting from this combination of BMW M1s prepared
for racing by Motorsport GmbH and those entered by private teams, and with the
cars driven by the big names in Formula 1 as well as ambitious racing drivers in
other categories, the Procar Series gained unique popularity. This is where the
world’s best drivers faced the old hands and newcomers in the scene, comparing
their skills with cars virtually identical in every respect. The crucial factor,
therefore, was driving skill – and this really caught the attention of the
crowd. The Procar races proved just as popular as the ensuing races for the
Formula 1 World Championship.
The recipe for success was perfectly prepared.
The fastest five Formula 1 drivers in the Friday practice sessions were placed
against 15 touring car specialists. With the Procar races held on the Saturday,
the first five places on the grid went to the stars. The remaining places were
shared by the touring car cracks lined up according to their practice times. And
they all joined in: Drivers and racing teams were happy to participate in the
Procar Series, provided they were not barred from doing so by their
contracts.
“Maybe I was so fast because I just wanted to drive a BMW.”
This is why on 12 May 1979, the Saturday before the Belgian Grand Prix in
Zolder, the two fastest drivers in practice were unable to take their seats in
the M1: Gilles Villeneuve and Jean-Pierre Jabouille had exclusive contracts with
other car manufacturers. But Jacques Laffite, the third-fastest driver in the
practice sessions, was just as happy to start his engine in BMW’s mid-engined
Gran Tourisme as Clay Regazzoni, the reigning World Champion Mario Andretti, as
well as Niki Lauda and Nelson Piquet.
Nelson, who later became Formula 1
World Champion with Brabham BMW and at the time No. 2 in the Brabham Team after
Niki Lauda, was unable to anticipate his great career back then when he said,
grinning: “Maybe I was so fast because I just wanted to drive a BMW.”
But Nelson’s competitors also had great names and a great reputation:
Hans-Joachim Stuck, who a day later came eighth in the Grand Prix racing for
the German ATS Team, the then reigning Formula 2 European Champion Bruno
Giacomelli, BMW Motorsport drivers Toine Hezemans and Dieter Quester, as well as
Elio de Angelis, another star in Formula 1. When the lights switched to green in
this truly outstanding line-up of Procar drivers, Hans-Joachim Stuck and young
Austrian star Markus Höttinger pulled away from the rest of the grid after just
a few laps. But in lap twelve the two of them got a little too close for comfort
and ended up in the fences. So to quote a report on the race summing up the 20
laps, “Italian driver Elio de Angelis proved to be the superman in the first M1
race, not only winning the event, but also completing the fastest lap. And this
was after starting from 15th place and plowing his way through the entire
field.” Second place went to Toine Hezemans, Clay Regazzoni finished
third.
The Procar Champions: Niki Lauda and Nelson Piquet.
Ultimately,
however, the initial results started to change in the course of the Procar
season, Niki Lauda, already two-time Formula 1 World Champion back then, scored
the largest number of points by the end of the season. In eight races in the M1
Procar Series, Niki scored three wins and finished second in one race. So while
Hans-Joachim Stuck was able to bring home victory in the last two races, he
ended up five points behind Lauda when the season finished. Clay Regazzoni held
on to his third place until the end of the season.
Winning the last three
races in the 1980 series, Nelson Piquet brought home overall victory in Procar
racing a year later, followed by Alan Jones and Hans-Joachim Stuck. Maybe this
was no coincidence, since Alan Jones, who later became Formula 1 World Champion,
was a dedicated fan of the M1 anyway, as one of the first customers to buy this
sports car for private use.
These spectacular events more or less marked the
end of the M1 in Group four racing for a simple reason: The M1 was only
homologated for racing on April 1st 1981 and the regulations were changed just
nine months later, making it virtually impossible for the M1 to compete any
more.
Boosted by up to 1,000 horsepower: Group five M1 with biturbo
power.
Even the success of the M1 in Group five was unable to match the
overwhelming Procar Series. Group five was for special production cars derived
from cars homologated in other racing categories – and that was virtually the
only restriction. The first M1s to enter Group five were powered by
normal-aspiration engines developing maximum output of almost 500 bhp. To cope
with engine torque of up to 800 Newton-meters or not quite 600 lb-ft, these cars
featured a Hewland FG 400 five-speed gearbox, with locking action on the final
drive ranging from 75–100 percent, depending on the racetrack. Later, the
engines of the Group five M1 were boosted up to 1,000 bhp by two turbochargers.
And to get as much of this huge power on to the road as possible, the body of
the car was modified by all kinds of spoilers turning the M1 into real “wing
monsters”. This was also when Team Schnitzer, the leading BMW tuning specialist,
turned a Group five M1 into the then most powerful racing car in the German
Motor Racing Championship, using a kevlar body on a specially reinforced
chassis. With this kind of power, Hans-Joachim Stuck came home first on both
Nürburgring and Salzburgring.
The IMSA GTO Champion in the USA: BMW
M1.
1981 was a spectacular year of success for the M1 in the USA. Any driver
wishing to play an important role at the time in the popular IMSA GTO
Championship simply had to drive BMW’s mid-engined coupe. After forming the Red
Lobster Team, Dave Cowart and Kenper Miller finished the season first and
second, naturally both at the wheel of a BMW M1. The white number 25 M1 won
twelve out of 16 races in the Championship. Only one driver among the top ten in
the 1981 Championship drove another car. The driver who finished seventh,
incidentally, was US racing legend Al Unser Jr., naturally at the wheel of an
M1.
Presenting art on fast wheels: M1 Art Car in the 24 Hours of Le
Mans.
The M1 was not only an outstanding racing and sports car, but also an
equally unique work of art. In 1979 world-famous pop art idol Andy Warhol tried
his hand on a ready-to-race M1 coupe, using his brush and paint to turn the M1
into one of the fastest works of art in the world.
This was BMW’s fourth Art
Car, a series of artistic achievements based on various BMW models. Warhol was
the first artist to paint the body of the car directly with powerful swipes of
his brush: “But the car is better than the art”, Warhol said himself afterwards
in a rather dry comment.
Boasting number 76, the BMW M1 Art Car struggled
for the title in Le Mans throughout the whole 24 hours, ultimately finishing the
race sixth.
Transplanting the M1 six-cylinder into production cars:
the M5 and M 635 CSi.
Production of the M1 ended in 1981 after a
production run of 445 units, 399 for the road and 46 in Procar trim. But the
heart of the M1, the M88 six-cylinder 24-valve power unit, was far too good to
retire from the scene. It was much too progressive and powerful. So in 1984
Motorsport GmbH once again hit the headlines, making aficionados of
high-performance cars wax lyrical once again when the 255 km/h (158 mph) M 635
CSi coupe and the M5 brought back the M1’s fast-revving power machine.
The
hand-built M5 quickly became a real legend. This was truly a wolf in sheep’s
clothing, with maximum output of 286 bhp almost three times as powerful as the
518i. At first sight it almost looked the same as its large-volume counterpart,
top speed of 245 km/h (152 mph) quickly captured the attention and admiration of
countless owners of large sedans and sports cars having to give way to the M5 on
the Autobahn even with the gas pedal pushed right down to the floor. Not
surprisingly, therefore, this marked the birth of the “Businessman’s
Express”.
Specifications BMW M1 – production model.
Engine
Water-cooled inline-six in mid-engine arrangement Four valves per cylinder, two
overhead cam-shaft with double roller chain drive
Capacity (cc)
3,453
Stroke (mm/in) 84/3.31
Bore (mm/in) 93.4/3.68
Max output (kW/bhp)
204/277 at 6,500 at rpm
Max torque (Nm/lb-ft) 330/243 at 5,000 at rpm
Max
engine speed (rpm) 7,000
Mean piston speed at max output (m/sec)
17.4
Compression ratio 9:1
Fuel supply Kugelfischer system mechanical fuel
injection three double throttle butterfly manifolds with six throttle
butterflies, dia 46 mm
Fuel grade (RON) 98
Fuel tank capacity (ltr.) (2 x
58) 116
Lubrication Pressure-circuit lubrication with dry sump oil system
Triple suction pump next to crankcase, pressure pump in the oil
sump
Electrical system.
Battery voltage (V) 12
Battery output
(Ah) 55
Alternator 14 V/65 A
Ignition Magneti-Marelli contact-free,
all-electronic digital ignition system controlled by the flywheel
Spark plugs
Bosch x 4 CS
Chassis and suspension.
Frame Spaceframe with plastic
body
Front axle Double track control arm (wishbone) with light-alloy wheel
mounts Independent suspension
Rear axle Double track control arm (trapezoid
arm at the bottom) with light-alloy wheel mounts Independent
suspension
Dampers/springs Bilstein gas pressure dampers Concentric coil
springs adjustable for height
Anti-roll bar dia (mm/in) front 23/0.91
rear
19/0.75
Brakes Inner-vented fixed-calliper disc brakes in two-circuit system
with brake servo pressure reducer on the rear axle
Brake disc dia(mm/in)
front 300/11.81
rear 297/11.69
Brake disc width (mm/in) front
32/1.26
rear 26/1.02
Swept brake area (cm²) front 96/wheel
rear
69/wheel
Parking brake Operated mechanically, acting on separate brake
callipers on the rear axle
Steering Rack-and-pinion steering, two-joint
safety steering column adjustable for reach
Steering wheel dia (mm/in)
360/14.2
Wheels Cast light-alloy wheels
front 7´´ x 16´´
rear 8´´ x
16´´
Tyres Pirelli P7
front 205/55 VR 16
rear 225/50 VR 16
Power
transmission.
Clutch F + S hydraulically operated, double-disc dry
clutch
Gearbox ZF five-speed manual gearbox with integrated final drive
Transmission ratios, manual gearbox:
1st 2.42
2nd 1.61
3rd
1.14
4th 0.846
5th 0.704
Reverse 2.86
Final drive
4.22
Dimensions (mm/in).
Wheelbase 2,560/100.8
Track, front
1,550/61.0
Track, rear 1,576/62.0
Length 4,360/171.7
Width
1,824/71.8
Height, unladen 1,140/44.9
Ground clearance, laden
125/4.9
Turning circle 13,000/512
Technical Description BMW M1
Group four.
Grand Tourisme based on international motorsport regulations.
Grand Tourisme cars are built in a small series and must have at least two
seats. They may be improved and modified in the interest of enhanced
performance. The modifications allowed for this purpose are specified in detail
in the International Motorsport Regulations.
In their looks and appearance,
Group four cars bear a close resemblance to the production
model.
Engine.
Six-cylinder in-line power unit, water-cooled, four
valves per cylinder, mechanical fuel injection, dry sump lubrication, oil cooler
at the front end of the car, 94 mm/3.70´´ bore, 84 mm/3.31´´ stroke, 3,500 cc
capacity, max output 345 kW (470 bhp) at 9,000 rpm, max torque 390 Nm (287
lb-ft) at 7,000 rpm.
Power transmission.
Hydraulically operated
double-plate clutch, ZF five-speed gearbox,
differential and gearbox cooling
system.
Chassis and suspension.
Double track control arms on the front
and rear axles, magnesium wheel mounts, aluminum wheel hubs with central bolt,
Bilstein dampers with bolted spring plates, anti-roll bars front and rear,
exchangeable and adjustable, ATE brake system, swing callipers and vented discs
front and rear, twin master brake cylinders, brake forces adjustable while
driving, rims 11.0 x 16 at the front, 12.5 x 16 at the rear, tyres 10.0/23.5 x
16 at the front, 12.5/25.0 x 16 at the rear, rack-and-pinion steering with
direct transmission ratio.
Technical Description BMW M1 Group five.
Special production car based on international motorsport
regulations.
Special production cars do not require a minimum production
volume, but must be derived from cars homologated in Groups one, two, three or
four. All modifications allowed on Group one to four cars as well as additional
Group five modifications are admissible, as specified by the International
Motorsport Regulations.
Greater freedom in the shape and dimensions of the
flared wheel arches as well as the use of aerodynamic improvements front and
rear significantly change the looks of the body.
Beneath the body shell the
manufacturer is able to choose and configure the various systems (engine,
transmission, suspension, brakes) with hardly any restrictions.
The Group
five BMW M1 features a 3.2-litre six-cylinder 24-valve power unit with an
exhaust gas turbocharger developing up to 850 bhp at 9,000 rpm. Boost pressure
is between 1.2 and 1.4 atmosphere.
The Group five version benefits from
technical optimisation of all units and systems. The car’s final specifications
will be published at a later date.
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