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2 Choosing an actuation system
Now one of the before mentioned systems will be chosen, based on the following criteria:
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Performance
Comfort
Cost
Packaging
Performance
The performance of a system is represented by its shift times. The faster a system can shift, the
better its performance. However manufacturers are always vague under which conditions the
given shift times are valid. This makes it difficult to predict how they will perform in a different
gearbox and different conditions, which can be less favorable. The following table with shift times
is therefore no more than a rough indication
Gearbox (car)
Min. shift time
BMW SMG II (M3 E46)
80 ms
Ferrari F1 (Maserati 4200GT)
80 ms
Ferrari F1 (360 F1)
150 ms
Ferrari F1 (Enzo)
150 ms
Bugatti Veyron (proposed)
200 ms
Ferrari F1 (575M)
220 ms
BMW SMG (M3 E36)
220 ms
Aston Martin Vanquish
250 ms
BMW SSG (3-series)
Alfa Selespeed (156 Selespeed) (old)
250ms (150ms for 1st to 2nd)
700 ms
Table 1: Shift times specified by manufacturer
In this table only hydraulically actuated systems are shown. In the following figure a comparison
concerning an unknown hydraulically operated gearbox and the electromechanically operated
gearbox “Easytronic” from Opel.
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