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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