TotalFocus
Why did you go for a wet clutch design when dry clutch is supposed to be cheaper and more fuel efficient?
That’s a very good question and we have spent a lot of time discussing it. At the end of the day, we have to have an effective product portfolio in terms of cost. With a dry clutch you cannot cover everything from 100 Nm to 500; in any case, if you want to be very sporty and have very high performance, you have to have a wet clutch. And at the opposite end of the scale, with very small engines we are beginning to recognize that many of them are coupled with quite heavy vehicles and that the thermal constraints on these small vehicles are sometimes greater than on a C or D-segment car.
Why precisely is this the case?
If you have a small engine which is unable to accelerate the vehicle’s mass, or accelerate it fast enough, you have to go for much more synchronizing time – and that obviously generates more thermal calories, which must be dissipated. So for very sporty cars with high torque you need a wet clutch, and for undersized engines in oversized vehicles you also need a wet clutch. There’s an area in the middle which works very well with dry clutch, and we have very effective ones in production today. But since we are developing a complete family [of DCTs] with shared technology and shared software, we made the clear decision to have commonality in terms of products. And with this new technology of pump-on-demand we don’t see any significant difference between wet and dry clutch [in terms of efficiency].
Does this mean dry clutch DCTs are finished?
I cannot speak for our competitors, but our new generation of DCTs at Getrag will be 100 percent wet clutch. However, our current [dry clutch] 6DCT250 is one of the very best for fuel efficiency and it will stay on the market for another six to eight years.
источник
Короче смысл в том что сухое сцепление подходит оптимально для С класса и атмосферных движков, для турбированных и движков с большим обьемом нужно мокрое сцепление, сами гетраги считают эту коробку удачной в своем сегменте, и планируют продавать до 2021 года. Так что о каком провале тут речь?