Boxster/Cayman (987) [Official] Porsche Cayman GT4
- Thread starter Betty Swollocks
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The Porsche 987 is the internal designation for the second generation Porsche Boxster sports car, built from 2004 to 2012.
In 2005, it was joined in the range by the new Cayman fastback coupé (project 987c). Production: July 2004–2012 (Boxster), August 2005–2012 (Cayman). It was succeeded by the Porsche 981 in 2012.
Since the 991 GT3 PASM dampers (first two pictures) are carried over to the GT4 (third picture):
I thought I would post a more comprehensive explanation on how those PASM dampers work because there's a LOT going on there. Just keep in mind that the official Cayman GT4's Nurburgring laptime (7:40 min) was set with the PASM on 'NORMAL' mode:
"Unlike conventional dampers, the PASM map-controlled damper also has an electrically actuated hydraulic bypass valve. The damping effect is provided by the oil in the damper flowing through a piston valve when the vehicle moves. The smaller the valve cross section, the harder the damping.
With the PASM damper, the oil can flow through a bypass valve, as well as through a fixed valve in the main piston. The flow can be increased or reduced by opening and closing the valve via a slide, producing continuous adjustment of the damper force. In the event of a system failure, the valve automatically closes. PASM is then in the hardest damper setting and thus the safest mode from a driving dynamics point of view (fail-safe principle).
Lane-change module
The damper forces at both axles are immediately increased in response to rapid steering movements, for example sudden evasive manoeuvres. This reduces body tilt and instability, thereby significantly improving vehicle control even in extreme situations.
Vertical-control module
In the Normal programme, the damper force is increased as soon as the vertical movement of the body, for example when driving over uneven surfaces, rises over a specific threshold value. This prevents body instability and therefore woolly driving behaviour. In the Sport programme, the damping is slightly reduced automatically to improve contact between the road and the wheels as body movements increase. This also results in a noticeable increase in comfort.
Lateral-acceleration module
If specific, speed-dependent thresholds for lateral acceleration are exceeded when cornering in the Normal programme, the damper force is increased by different, defined amounts for each side of the vehicle. This prevents vehicle instability and significantly increases driving precision. In the event of large vertical movements and high lateral acceleration coinciding, the higher of the vertical-control and lateral-acceleration damping values is set. This happens if, for example, the damping in the Sport programme was previously decreased by the vertical-control module.
Brake module
PASM switches to harder damping at the start of a braking operation to reduce vehicle nose-dive when braking. This way, higher brake forces can be transmitted to the road faster. It switches back to a softer setting (this setting is different for the front and rear axle) after a specific amount of time. The result is improved road contact, and thus a shorter braking distance, particularly when braking on uneven surfaces.
Load-change module
The damper characteristics for the front and rear axle are individually switched when accelerating heavily, releasing the throttle or changing lanes. In Normal mode, the dampers are briefly switched to a harder damping setting in these driving conditions. This avoids excessive lifting or diving at the front of the vehicle (“pitching”). In Sport mode, a softer damper characteristic is briefly selected if necessary to improve traction when accelerating, particularly on uneven surfaces.
The PASM system comprises the following components:
• Four dampers with continuously adjustable damping force (each with one bypass valve)
• PASM control module
• Two acceleration sensors for detecting vertical movement of the body (one at the damper dome at the front right and one at the rear left). Further signals such as lateral acceleration, steering angle, travel speed, brake pressure, engine torque, etc. are read in via the CAN bus. The system measures body movements via one acceleration sensor on each axle (front and rear). Values such as lateral acceleration, steering wheel angle, vehicle speed and information on possible braking operations are provided by the PSM via the CAN bus. Engine rpm and torque values are provided by the Motronic via the CAN bus."
I thought I would post a more comprehensive explanation on how those PASM dampers work because there's a LOT going on there. Just keep in mind that the official Cayman GT4's Nurburgring laptime (7:40 min) was set with the PASM on 'NORMAL' mode:
"Unlike conventional dampers, the PASM map-controlled damper also has an electrically actuated hydraulic bypass valve. The damping effect is provided by the oil in the damper flowing through a piston valve when the vehicle moves. The smaller the valve cross section, the harder the damping.
With the PASM damper, the oil can flow through a bypass valve, as well as through a fixed valve in the main piston. The flow can be increased or reduced by opening and closing the valve via a slide, producing continuous adjustment of the damper force. In the event of a system failure, the valve automatically closes. PASM is then in the hardest damper setting and thus the safest mode from a driving dynamics point of view (fail-safe principle).
Lane-change module
The damper forces at both axles are immediately increased in response to rapid steering movements, for example sudden evasive manoeuvres. This reduces body tilt and instability, thereby significantly improving vehicle control even in extreme situations.
Vertical-control module
In the Normal programme, the damper force is increased as soon as the vertical movement of the body, for example when driving over uneven surfaces, rises over a specific threshold value. This prevents body instability and therefore woolly driving behaviour. In the Sport programme, the damping is slightly reduced automatically to improve contact between the road and the wheels as body movements increase. This also results in a noticeable increase in comfort.
Lateral-acceleration module
If specific, speed-dependent thresholds for lateral acceleration are exceeded when cornering in the Normal programme, the damper force is increased by different, defined amounts for each side of the vehicle. This prevents vehicle instability and significantly increases driving precision. In the event of large vertical movements and high lateral acceleration coinciding, the higher of the vertical-control and lateral-acceleration damping values is set. This happens if, for example, the damping in the Sport programme was previously decreased by the vertical-control module.
Brake module
PASM switches to harder damping at the start of a braking operation to reduce vehicle nose-dive when braking. This way, higher brake forces can be transmitted to the road faster. It switches back to a softer setting (this setting is different for the front and rear axle) after a specific amount of time. The result is improved road contact, and thus a shorter braking distance, particularly when braking on uneven surfaces.
Load-change module
The damper characteristics for the front and rear axle are individually switched when accelerating heavily, releasing the throttle or changing lanes. In Normal mode, the dampers are briefly switched to a harder damping setting in these driving conditions. This avoids excessive lifting or diving at the front of the vehicle (“pitching”). In Sport mode, a softer damper characteristic is briefly selected if necessary to improve traction when accelerating, particularly on uneven surfaces.
The PASM system comprises the following components:
• Four dampers with continuously adjustable damping force (each with one bypass valve)
• PASM control module
• Two acceleration sensors for detecting vertical movement of the body (one at the damper dome at the front right and one at the rear left). Further signals such as lateral acceleration, steering angle, travel speed, brake pressure, engine torque, etc. are read in via the CAN bus. The system measures body movements via one acceleration sensor on each axle (front and rear). Values such as lateral acceleration, steering wheel angle, vehicle speed and information on possible braking operations are provided by the PSM via the CAN bus. Engine rpm and torque values are provided by the Motronic via the CAN bus."
Porsche Guy
Kraftkurve King
Very soon....
Someday PDK will "grace" the GT4 but not that soon. Demand for the manual has been strong with GT4 production sold out before it hit showrooms.
Sunny
Premium
No, I meant a track only GT4 Cup or GT4R.
According to the person who talked to Andres Prueninger, he said no GT4 RS since it would be too close to the GT3. Of course, all Internet chat - http://www.planet-9.com/981-cayman-gt4-chat/110889-met-andreas-preuninger-weissach.html#post982069, so caveat lector.
Sunny
Premium
^Not a GT4 (the car) though, it is Cayman/Cayman S build by some private team to race in the GT4 class - http://gt4series.com/prosport-performance-to-enter-gt4-european-series-with-porsche-981-cayman-sp/
Soup
Premium
RSP-Motorsports Inc. performed a Dynoperformance Test on a 2016 Cayman GT4.
Stock Flywheel Horsepower is 385HP@7400rpm.
Outstanding Performance!! 404HP at the Flywheel.
Stock Flywheel Horsepower is 385HP@7400rpm.
Outstanding Performance!! 404HP at the Flywheel.
The Pretender
Turbo Tüftler
The Pretender
Turbo Tüftler
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Porsche
Dr. Ing. h.c. F. Porsche AG, is a German automobile manufacturer
specializing in high-performance sports cars, SUVs, and sedans,
headquartered in Stuttgart, Baden-Württemberg, Germany. Owned by
Volkswagen AG, it was founded in 1931 by Ferdinand Porsche.
In its early days, Porsche was contracted by the German government
to create a vehicle for the masses, which later became the Volkswagen
Beetle. In the late 1940s, Ferdinand's son Ferry Porsche began
building his car, which would result in the Porsche 356.
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