The type 917
Of all of the historic racing Porsches,
without doubt the best remembered, and the most important was the Porsche
917 which debuted in 1969 as a 4 5-liter, 550 horsepower, twelve-cylinder
version of the 908. In 1970, the developed 917 not only brought
Zuffenhausen its second straight World Makes crown, but its first ever,
outright victory at Le Mans. In subsequent seasons, the coupe would be
transformed into a 1000 HP. turbocharged, open topped Spyder that would
come to dominate the North American Can-Am series much in the same
fashion as it had the endurance scene. In short, the 917 was a watershed
car that put Porsche in the center stage spotlight of motorsport.
Piech and his group created the 917 after
discovering a rules loophole big enough to sink 20 Titanics That
regulatory miscue permitted so-called "production" 5.0-liter
sports cars, of which at least 25 identical examples had to have been
made, to run in the Manufacturers title chase. The idea that this figure
would permit such aging vehicles like the Lola T-70 coupe and the Ford
GT-40 to flesh out the relatively slim 3.0-liter prototype ranks in the
championship. Never did anyone think that someone would go to the trouble
of building 25 expensive prototype-like vehicles simply to qualify them
as "production" legal.
Yet, in the spring of 1968 that's
exactly what Piech and Porsche decided to do. The reasoning behind the
decision was not complicated, since Porsche already was building twice
that many competition cars a year to meet the internal decree that new
racers would be used by the factory for every event. Further, Piech
reasoned that the 917 wouldn't have to be created from scratch, but
could be developed from the just introduced 908 eight-cylinder.
In fact, while the 917 was largely new,
much of its major components could be traced to the 908. This included
its awesome twelve-cylinder powerplant that kept the 908's basic head
design, injection system, and bore and stroke dimensions. New was the
central power pick up arrangement which effectively created two six
cylinder crankshafts tied together - thus eliminating the torsion
problems found with a more conventional arrangement. Fortunately, from
the start, the engine, which would eventually be produced in 4.9, 5.0 and
5.4-liter displacement variants worked well from the beginning.
Less successful was the transformation of
the 908's chassis that kept its overall shape and wheelbase. The only
real changes were the substitution of a detachable tsail that permitted
the car to be raced either as a "langhect" or in
"Kirtz" fashion, as well as the placing of the driver slightly
further toward to accommodate the extra length of the new flat 12.
Unhappily, while the 908 was fairly stable, the 917 was not, especially
approaching the 220 plus mile-an-hour speeds of which it was capable.
Ultimately, this was traced to an
aerodynamic problem that caused the rear of the car to lift creating
severe high speed oversteer. Testing produced the upraised wedge tail
shape that came to so characterize the tamed 917K models, this being
discovered during a post 1969 shakedown run conducted by Porsche and the
Gulf Wyer team which was to represent the factory in 1970-71.
With its aerodynamics corrected, the 917
went on to dominate the World Championship of Makes against the almost
equally awesome 5 0-liter Ferrari 5l2. Likewise the 25-example
"production" sports car by the Italian marque. Ironically,
while the 917 won Le Mans both years, it wasn't the Wyer team that
triumphed. Instead, the Porsche Salzburg team belonging to Piech's
month Louise, with Englishman Richard Attwood and longtime factory driver
Hans Kerrmann driving scored the initial victory. Hans Kerrmann retired
after the event.
The second win came at the hands of the
Martini team that succeeded the Porsche Salzburg operation in 1971.
Interestingly, despite the fact that Porsche had developed a special long
tail version of the 917 for Le Mans with a top speed of nearly 250
miles-an-hour, the two victories were scored by short tail 917K's.
That latter performance came with a magnesium-framed version, which was
used as a testbed for what Porsche hoped, would be its 1972 Can-Am
challenger.
As far back as 1969, Zuffenhausen had
become involved in the Can-Am when, at the urging of its North American
racing boss, Josef Hoppen, it created an open-topped version of its
endurance coupe for the championship. Although the car was overweight and
under powered, Jo Siffert drove it to fourth place in final point
standings. Later four more coupes were cut down to race in the
European-based Can-Am counterpart, the Interserie that would eventually
become a 917 preserve.
In the spring of 1971 Piech and Porsche
became seriously interested in the Can-Am, producing a revised version of
the 917 Spyder dubbed the 917/10. Lighter in weight, this was intended to
utilize a turbocharged 5.0-liter twelve-cylinder, but initialed appeared
in Siffert's hands during 1971 with a non-boosted engine instead.
Again, despite a power handicap, Siffert took fourth in the standings.
Unfortunately, the Swiss was killed before
the end of the season in a Formula One accident. Originally Porsche had
planned to involve Siffert in the '72 Can-Am as a back up to Mark
Donohue who would spearhead Porsche's efforts in the Roger Penske
L&M sponsored 917/10. In the end, Penske alone represented the
factory, although numerous privateers raced non-turbo versions of the
Spyder both in the Can-Am and the Interserie during the 1972 campaign.
Porsche had little trouble defeating the
reigning McLaren's in North American, and equally little problem
capturing the Interserie. However, Donohue would have to wait a year for
the Can-Am driver's crown, having been put out of action for most of
the year after a testing accident at Road Atlanta. Donohue injured his
knee when the tail section came off his car, causing it to flip
violently; instead substitute George Follmer garnered the honors.
Donohue would return in 1973 using a
revised Spyder, the 917/30 that featured a longer wheelbase and revised
aerodynamics. Powered by a 5.4-liter turbo, the Sunoco Oil company-backed
entry was capable of 240 MPH in a straight line. Although the first two
Can-Am rounds went to privateers using the previous year's 917/10,
Donohue came back strongly, winning everything else from the third race
on. At the end of the season he announced his retirement, while the SCCA
forced the withdrawal of the 917 from Can-Am competition by drastically
reducing its fuel supply, forcing it to race at noncompetitive boost
pressures.
Still, the saga of the 917 wasn't
quite finished. While it raced on in the Interserie, winning the 1974
crown and helping Porsche to take the 1975 championship, it also made one
more Can-Am appearance. That came at Mid Ohio in 1974 when Brian Redman
took the Penske 917/30 to a second place behind the Shafdow Chevrolet of
Jackie Oliver. In 1975, ten days before his tragic death during practice
for the Austrian Grand Prix, a now un-retired Donohue used that same car
to set a new closed course speed record of more than 221MPH at the high
banked 2.5-mile Talladega Tri-oval, and, that still wasn't it. In
1981, the Kremer brothers entered a 917 endurance coupe copy in the Makes
series, the car showing great competitiveness in spite of its aged
design.
The Production Cars
After it put aside the Gmund coupes
following the 1954 season in favor of the competition-oriented 550
Spyders, Porsche did not totally abandon the production car arena. During
the latter part of the 1950's Zuffenhausen installed four cam Carrera
four-cylinder powerplants in a number of different 356's specifically
so that its customers would have something to run in the production
categories. Included were both the open-topped Speedsters and their coupe
counterparts, some of these cars remaining competitive enough to win in
North American SCCA Regional and National club events up through the
1980's.
The ultimate expression of the 356
production racer was the Carrera Abarth of the early 1960's. This was
a four-cam 356 mated to a lightweight Italian alloy body designed by
Zagalo and built under contract for Porsche through Austrian expatriate
Carlo Arbarth. These cars, about 20 in all, were not only used by
Porsche's customers, but by the factory itself in both international
and national events, including Le Mans where it won its class multiple
times.
In 1965, the factory switched its
concentration on the four-cylinder 356, to the just introduced
six-cylinder 911, debuting the new coupe at that year's Monte Carlo
Rally with a top five finish. Although the 911 would go on to make a name
for itself in rallying - including winning at Monte Carlo on multiple
occasions, and although it would do well in road course action also,
development of the 911 as a race car was largely ignored by the factory
until the 1970's
Even so, in private hands the 911 did well
throughout the world, winning its class at Le mans as well as in the
prestigious North American Trans-Am championship, and in the
International Motor Sports Association's Camel GT. In 1967,
Piech's engineers put together the 911R, the only attempt producing a
lightweight 911, as a technical exercise. Never built in enough numbers
(again there were between 20 and 25 made), the 911R, which featured a
stripped interior and fiberglass fenders, doors and deck lids, was forced
to run as a "prototype". Nevertheless, it created a legend of
what "might have been" that would provide a foundation for
later racing 911 models.
Late in 1969 the factory produced around
35 lightweight body shells. These would be used to build up both circuit
racing and rally 911 through 1972. Although Porsche never gave these
light weights their own designation, referring to them only as
"911S's", unofficially they were dubbed "911
ST's". In their final, 1972 form, they were raced with 2.5-liter
flat sixes, which used many parts from the Carrera 906 program. Perhaps,
more important than their record was the fact that they served as a
foundation for what came next, the Carrera RSR.
Developed under famed Porsche engineer
Norbert Singer in 1972, after Piech had left the family firm, the Carrera
RSR was the first true effort at creating a production 911 that could
dominate the arena. Although it was lighter in weight than previous
911's, it did not go to the extreme that the 911A did, still it
featured a number of fiberglass panels including bumpers and deck lids.
In fact, two of the distinguishing features of the Carrera RSR when it
was introduced in 1973 its ducktail rear spoiler and front bumper spoiler
configuration, the latter unit having a center mounted oil cooler. In
1974, the Carrera RSR was revised slightly with a rear "whale
tail" spoiler and new front bumper arrangement. The latter because
of U.S. mandated changes in bumper regulations for the street beginning
that year.
In terms of its fuel injected engine, the
Carrera RSR was fairly standard stuff, not differing much from what had
come before except for an increase in displacement. Originally raced in
2.7-liter form, its engine size rose first to 3.8 liters and then to 3.0
Liters. Regardless, the Carrera RSR dominated the production car scene
from 1973 through 1975, wining the Daytona 24 Hours three times outright
before ending its career in 1977. Additionally it won both the IMSA Camel
GT and European FIA GT championships during that period, as well as a
host of individual race triumphs, including the Targa Florio in 1973.
That latter victory came with a specially
modified RSR run by the factory in Martini colors as a prototype. The
following year Singer took things a step further, producing a
turbocharged RSR with revised aerodynamics that included a raised rear
roof and a huge rear wing. With this car, also backed by Martini, Porsche
finished second at Le Mans, the highest placing ever for an RSR. The
reason for the coupe's existence was the upcoming so-called
"silhouette" prototype Formula that would be instituted in 1975
for the World Makes Championship,
Porsche planned to enter that series, with
the much-modified 911-based 935, producing a less radical version for its
customers called the 934. To gain experience the Turbo RSR was built as a
"proof of concept" prototype. How well that worked can be seen
In the fact that the 935 dominated the scene, winning the Manufacturers
chase from 1976 through 1979, and the IMSA Camel GT up through 1972.
During that same period both the 934 and the 946 won the Trans-Am crown
as well as the German National championship and numerous other region
series. Perhaps the high point of the 935's career came in 1979 when
it won Le Mans outright, the first production-based car to do in more
than two decades.
For all of its accomplishments, what the
935 will be most remembered for was its appearance. Planned to emulate
the shape of the road-going 930, the appearance quickly changed when
Singer found a loophole that allowed him to place the headlights in the
bump, thus creating the first "slope" nose, which improved
front-end downforce. Before the 935 exited the scene in 1984, it had
acquired fully covered doors, a raised roar roof, sophisticated rear
aerodynamics, and underneath its skin, a full tubeframe chassis structure
Moreover, what the factory had produced
inspired Porsche entrants to create their own 935's using the
drivetrain as well as suspension and brake parts from Zuffenhausen as
their foundations. And, if the 935 was dominant, so too was the 934,
which won Sebring in 1963, on its way to the Camel GTO title that season.
All in all, the 935's and 934's represented the fastest and
wildest 911's ever made.
But, they weren't the only modern
production Porsche race entries. In 1970, Porsche introduced the
competition version of its mid-engine, 914/6 roadster, the 914/6GT that
won its class at Le Mans. The next year in the hands of Peter Gregg and
Hurley Haywood, it would claim the inaugural Camel GT championship, going
on to later win several Camel GTU crowns as well. The model was also
active in SCCA National competition, and in international rallying,
although it never achieved the success in either venue that it did in
professional, high-end international circuit competition.
In 1979, the 914's successor, the 924
was introduced into racing, running initially in North America with the
SCCA, where in 1980 it won the first of several National crowns. Also
that year, a turbocharged version was run at Le Mans with some success.
Subsequently, turbo 924 GTR's would win in the Trans-Am and IMSA,
claiming, as did the 914, multiple GTU class title for itself. Also raced
with some success, was the 944 Turbo GTR, which at one point was
Porsche's mainstay entry in the Trans-Am. However, a lack of
development of the latter car wound up severely stunting its career.
More recently Porsche produced the
turbocharged, 993-based 911 GT2 eacer~m which cleaned house on the
international production scene during the mid-1990's, and latter, was
nearly unbeaten in the IMSA Exxon Series production arena. In 1998,
Porsche introduced the GT class 911 GT2R at Le Mans where this 996-based
coupe promptly won its class. In 2000, the 911 GT3R was unstoppable
winning wherever it raced, claiming both the American Le Mans Series and
Grand American Racing Series GT category crowns. For 2001 Porsche has
introduced an improved version, the 911 GT3RS which is expected to
continue what its predecessor has started.
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