Mechanical Timepieces
The Porsche Fuhrmann Engine (Type 547) was named after its inventor Ernst Fuhrmann, and built from 1953 to 1964. The Type 547, also called “drawer engine”, is an air-cooled four-cylinder boxer engine with four overhead camshafts that are powered by four vertical shafts. The crankcase, cylinder and cylinder heads of the engine are made of aluminum alloy. The special feature of this engine is its small size and low weight, which is achieved by the materials used and the clever construction.
Porsche has always been known for its outstanding transmission units. This is no different with the Porsche Tiptronic, the predecessor of the Porsche dual-clutch transmission (PDK). The Tiptronic, which can also be operated automatically or manually as needed, is a good combination of both worlds.
The development of the Porsche Tiptronic transmission was based on the Porsche dual-clutch transmission (PDK) used in 1984 in the Porsche 962 racing car. For the first time in 1990, Porsche used the term ‘Tiptronic’ for the four-speed automatic transmission available with the Porsche 964 Carrera 2. Previously, there was the semi-automatic “Sportomatic” from 1968 to 1980. In 2008, the street version of the Porsche PDK dual-clutch transmission replaced the Tiptronic in most of the sports car models.
☞ Although the brand name ‘Tiptronic’ belongs to Porsche, it has also been used by Volkswagen and Audi.
With the version Tiptronic S, which was first used in the 1995 model of the Porsche 993, shift paddles werde added to the steering wheel. The function of the manual shifting was thereby transferred from the shift knob additionally to the steering wheel, which was not usual at the time. After the introduction of the PDK, the Tiptronic S was mainly used on the Porsche Cayenne.
Among sporty Porsche drivers, for whom driving pleasure plays an important role, Tiptronic is not very popular. It does not meet the requirements of many enthusiasts with its switching times and the switching behavior. In contrast to the PDK transmission, which is pretty successful with its excellent shifting times, many buyers prefer the traditional manual transmission instead of the Tiptronic. Nevertheless it’s a good transmission, and on this point one should not forget that Porsche purists are generally skeptical of any kind of vehicle component with the terrible additional designation ‘Automatic’.
For every Porsche fan, the three letters ‘PDK’ carry a magical meaning. This could be partly because they abbreviate a complicated German term like ‘Porsche Doppelkupplungsgetriebe’. On the other hand, it is due to the seven speed dual clutch transmission technology behind it.
The PDK dual-clutch transmission is in principle an automated gearbox, which enables automatic gear changes without power interruption thanks to two sub-transmissions. The gears are either sorted automatically or selected by the driver via the shift paddles on the steering wheel or by tapping the gear lever. In contrast to conventional automatic transmissions with hydraulic torque converter, the transmission of the torque takes place via one of two clutches which connect two partial transmissions to the drive. While the driving force is transmitted to the wheels via a clutch and the first partial transmission, the next gear is engaged in the second partial transmission. When changing gear, one clutch is opened, the other closed simultaneously. While one of the partial transmissions carries the even gears, the other takes the odd ones. The gears are already engaged when shifting, so that the traction is not interrupted when changing gear. This principle allows, like in an automatic transmission with hydraulic torque converter, a gear change in milliseconds.
The first six gears of the PDK have a sporty gear ratio, which means that the maximum speed is reached in sixth gear. In seventh gear, the long gear ratio lowers the engine speed, which optimizes fuel consumption.
The operation of the Porsche PDK largely corresponds to the handling of other fully automatic transmissions. The intervention of the driver is only required when driving off, reversing and parking. On request, the driver can also change the gears manually by using the shift paddles on the steering wheel or by tapping the gear knob.
In the 1980s, Porsche introduced the dual-clutch transmission for racing. The Porsche 956/962 was the first to be equipped with the PDK transmission, and thus achieved great success. With its 54 victories, the 962 is still one of the most successful racing sports cars Porsche has ever built. Since the technology and the computer capacities were still very limited, the serial development was not pursued at that time. In 2008, the PDK dual-clutch technology was transferred to the streets, and replaced in the Porsche 911 the previous automatic transmission ‘Tiptronic S’. At the time of its introduction, the PDK was up to 60 percent faster at shifting gears compared to other automatic transmissions. Following the Porsche Carrera, which was the first to get the new dual-clutch transmission in 2008, a year later the transmission was also offered with the Boxster and Cayman models.
One of the popular features of the Porsche PDK is the launch control. It enables optimal acceleration during start-up, preventing the tires from spinning through ideal power transmission. The engine speed is leveled for maximum drive without loss of traction.
☞ In 2011, the Porsche 911 991 introduced a 7-speed manual transmission based on the 7-speed dual-clutch transmission. The top speed is achieved as in the PDK in sixth gear, after which the seventh gear is used to save fuel.
In 2013, the PDK was improved in its speed and performance, and installed in its new version in the Porsche 911 GT3. In addition to lighter gears and wheelsets, which make the transmission about two kilograms lighter, it has shorter gear ratios. Unlike the usual PDK, where the seventh gear is used to save fuel, the GT3 reaches the top speed in seventh gear. The later model of the popular sports car was also offered on request of many enthusiasts with a newly developed 6-speed manual transmission. Although the PDK with launch control accelerates the GT3 by 0.5 seconds faster than the manual transmission to 100km/h, has shorter shift times, and is offered at the same price, many still choose the ‘slower’ manual variant. The good old manual transmission is not so easily beaten. With intermediate accelerations from low speeds on the circuit, in many cases it proves to be at least as fast as the PDK.
An important question Porsche buyers often face is whether they should buy their car with PDK or manual transmission. For the hardcore purists nothing can replace the mechanical feeling you experience when changing the gears with a traditional shift knob. For others, the small bit of additional performance that the PDK offers is in the foreground. When it comes to launching, the manual can’t match the precision of PDK’s clutch control. Many do not care, because in this case you can not use your driving skills. However, you can’t go wrong with the precise PDK, which can also be operated manually in a certain way.
In the case of a used car purchase, the PDK can serve the buyer as an assurance for a durable gearbox. With a manual transmission there is always the risk that the teeth on the transmission cogs were worn out due to faulty gear changes.
It should be appreciated, however, that Porsche (still) offers its sports cars with a manual transmission. Maybe these are the last of their kind. Many other sports car manufacturers like Ferrari or Lamborghini have already discontinued these gearboxes, and only install dual-clutch drivetrains. This is partly because their clientele hardly chooses the manual option. Thus, the Porsche enthusiasts are the last of their kind who can still proudly carry out the gear change themselves.
☞ If you want to know how to pronounce ‘Porsche Doppelkupplungsgetriebe’ in German, you can watch it here:
Porsche ist seit jeher eng mit dem Motorsport verbunden, und kehrte 2014 nach einer langen Auszeit mit dem 919 Hybrid Prototypen auf die Piste in Le Mans zurück. Für die FIA-Langstrecken-Weltmeisterschaft werden Anforderungen in Sachen Sicherheit, Effizienz und Nachhaltigkeit gestellt, was unter anderem auch die Hybrid-Technologie beinhaltet. Als Weltmeister und Titelverteidiger dient der Porsche 919 Hybrid auch als technologischer Wegweiser für die straßenzulässigen Brüder Boxster und Cayman.
Angetrieben wird der 919 Hybrid von einem 2.0 Liter V4-Ottomotor mit Turboaufladung und einem zusätzlichen Elektromotor.
Der Verbrennungsmotor mit Direkteinspritzung ist kompakt und hocheffizient. Die Brennraumgeometrie ähnelt dabei dem des Porsche 918 Spyder. Während das Fahrzeug eigentlich heckgetrieben ist, wird beim Beschleunigen der elektrische Antrieb an die Vorderräder zugeschaltet, sodass temporär alle Räder angetrieben werden.
Die elektrische Motor-Generator-Einheit befindet sich an der Vorderachse, und wird von einem wassergekühlten Lithium-Ionen-Akkumulator mit A123 Systems Zellen gespeist. Das Hybrid-Systems ist mit zwei Energierückgewinnungssystemen ausgestattet. Das erste System sorgt durch eine Rekuperationsbremse an der Vorderachse für eine Rückgewinnung der Bremsenergie. Das zweite System treibt mit dem heißen Abgasstrom einen Generator mit der Turbo-Compound-Technik an, wodurch zusätzlich elektrische Energie gewonnen wird.
Die Leistung des Verbrennungsmotors wird von Porsche mit über 503 PS (370 kW) angegeben. Der Elektromotor in der Front hat den Angaben zufolge seit der Konfiguration im Jahre 2015 eine Leistung von mehr als 400 PS (294 kW). Mit beiden Antriebseinheiten zusammen kommt das Fahrzeug auf eine gesamte Systemleistung von ca. 900 PS.
Zum Vergleich: Toyota gibt die Leistung des TS050 Hybrid mit 1.000 PS an.
Die Beschleunigung auf 100 km/h legt der LMP1-Prototyp von Porsche in 2,8 Sekunden hin. Für 200 km/h brauch er lediglich 4,8 Sekunden.
Die Radführung des Fahrwerks hat vorne und hinten Einzelradaufhängungen an Multilinks. Verwendet wurde dabei das Pushrod-System mit einstellbaren Stoßdämpfern. Gelenkt wird das ganze über eine hydraulisch unterstützte Zahnstangen-Lenkung.
Das Monocoque des Porsche 919 Hybrid ist eine Verbundfaser-Konstruktion aus Carbonfasern mit Aluminium-Wabenkern. Die Seiten sind durch zusätzliche Panels gegen Unfälle gesichert. Neben der Materialwahl tragen auch die komplexe Konstruktion der Einzelteile für eine hohe Belastbarkeit und ein optimales Systemgewicht bei.
24h von Leman 2017: Der Hattrick von Porsche
The Porsche Cayman 981 c replaced its predecessor model 987c in 2013, and was produced until 2016. In addition to the basic model of the Cayman, the model variants Cayman S, GTS and GT4 were available. Similar to its predecessor, the 981c is based on the same technical platform as the Porsche Boxster of its generation.
Paired with a lighter body than its predecessor, the 981 generation also comes with a bit more power. The naturally aspirated 275hp (202kW) 2.7-liter flat-bodied boxer engine of the base model accelerates the 1310-kilogram Cayman from zero to 100km/h in 5.7 seconds, reaching a top speed of 266 km/h.
The Cayman S, in contrast, with its 325hp 3.4-liter engine, which is also installed in the Porsche 911 Carrera, puts the acceleration to 100km/h in 5.0 seconds. 370 Newton meters are thereby brought from the rear axle onto the road. The top speed is 283km/h.
In the following years, the two more powerful variants Cayman GTS and Cayman GT4 were introduced by Porsche. The GT4 was equipped with the water-cooled 3.8-liter boxer engine from the Porsche 911 Carrera S (991). The chassis, on the other hand, has been largely taken over from the Porsche 911 GT3 (991).
Due to the mid-engine concept the Cayman has two luggage compartments. It offers 150 liters of storage space in the front, and up to 160 liters in the back. The disadvantage of the rear trunk space is that it is heated up by the heat of the engine. Therefore, heat sensitive things like food should preferably be stowed in the front.
The advantages of the mid-engine layout are evident in the excellent handling and sporty driving dynamics. Many car manufacturers have therefore used the Cayman as a benchmark for their own sports cars. The arrangement of the engine immediately behind the front seats ensures centralization of the mass, whereby drive influences are minimized. The coupe offers a sporty gait and has due to the fixed roof a higher torsional stiffness than the Porsche Boxster.
Distinctive to its predecessor 987, the Porsche Cayman 981 has wider side air intakes. In addition, prominent lines were added to the body sides leading to the air intakes.
As with the other models, Porsche has also switched from hydraulic to electromechanical steering on the Cayman 981. This makes the steering easier and more pleasant in everyday life than on its predecessor. The action of the electric steering is felt in a jerky braking on uneven ground. If you take your hands off the steering wheel (we do not recommend it), the active steering interventions help to stabilize the vehicle. Nevertheless, the feedback of the steering behavior is pithy enough to satisfy even purists.
The interior of the Cayman looks and feels high-quality and is designed with lots of leather and brushed aluminum. The dashboard has no differences to the remaining Porsche models. Porsche-typical is the positioning of the ignition key. Due to the racing history in Le Mans it’s on the left side of the steering wheel. Most controls and switches are functionally aligned on the right side.
The flat roofline was rounded off slightly at the rear, while the front was made more aggressive in the comparison to the 987 generation.
On the basis of the Cayman 981c in 2015 the Porsche Cayman GT4 was introduced to the market. With 385 hp and a maximum speed of 295 km/h, the naturally aspirated engine without turbos transmits 420 Newton meters to the crankshaft. This makes him the sportiest and most powerful Cayman to date. The distinctive optical feature to the previous Cayman models is a rigid rear spoiler is installed. This allows a maximum pressure of 100 kilograms, and reminds you every time you look in the rearview mirror that you are sitting in a thoroughbred sports car.
The Porsche Cayman 981 GT4 on the Nürnburgring
The GT4 is equipped with the water-cooled 3.8-liter boxer engine from the Porsche 911 Carrera S (991). Since the water-cooled six-cylinder is installed as a mid-engine in the GT4, it had to be rotated by 180 degrees to be connected to the transmission. For reasons of space, further modifications to the intake tract and the exhaust system had to be made, whereby the performance compared to the Carrera S was somewhat throttled.
The chassis of the Cayman GT4 has been largely taken over from the Porsche 911 GT3 (991). The braking system of the GT3 is expected to provide more than enough braking power for the 90 kilogram lighter Cayman. While Porsche delivered the 911 GT3 only with a dual-clutch PDK, it’s the exact opposite with the Cayman GT4. In favour of the hardcore fans the GT4 is only built with a manual transmission.
The built-in manual gearbox saves the Cayman GT4 a little weight, but still makes a small smear in the acceleration. Manually changing the six gears takes more time than the PDK would require. So it takes around 4.4 seconds to 100km/h with the GT4, which is far from a bad value in itself. And since purists prefer to sort the gears themselves, this is not a real disadvantage. After all, in the not-too-distant future, self-driving cars will even take away the steering. Until then one may quietly enjoy the time in which you as a driver still have the control over the car.
The interior is designed in the classic Porsche style with sportiness in mind. One small detail stands out when opening or closing the doors. For that you have to pull on a colourful door lash, instead of a normal door handle. According to the manufacturer this is due to weight reasons. The racing steering wheel is free of any buttons and covered with Alcantara. The rest of the interior is held in alternation with leather and Alcantara relatively simple.
In the summer of 2016, Porsche completely revised the Cayman, and introduced the series 718 (Type 982). The successor of the 981 comes with new 4-cylinder turbo engines. This puts an end to the beloved 6-cylinder engines due to the current downsizing measures in the automotive industry. Similar to the two predecessors, the 718 Cayman has the same technical platform as the Porsche 718 Boxster. While the earlier generations (987 and 981) were offered at a higher price than the Boxster, the new series has become Porsches entry level sports car.
