Clutch Industries Dual Clutch Transmission Clutch Kit DC3173N

A dual-clutch transmission eliminates the torque converter as used in conventional epicyclic-geared automatic transmissions. Instead, dual-clutch transmissions that are currently on the market primarily use two oil-bathed wet multiplate clutches, similar to the clutches used in most motorcycles, though dry-clutch versions are also available. The first series production road car with a DCT was the 2003 Volkswagen Golf Mk4 R32. In DCTs where the two clutches are arranged concentrically, the larger outer clutch drives the even-numbered gears and the smaller inner clutch drives the odd-numbered gears. Shifts can be accomplished without interrupting torque distribution to the driven roadwheels, by applying the engine's torque to one clutch at the same time as it is being disconnected from the other clutch. Since alternate gear ratios can preselect an odd gear on one gear shaft while the vehicle is being driven in an even gear (and vice versa), DCTs are the fastest-shifting road car transmission available. DCTs can shift more quickly than cars equipped with single-clutch automated-manual transmissions (AMTs), also called single-clutch semi-automatics. Also, with a DCT, shifts can be made more smoothly than with a single-clutch AMT, making a DCT more suitable for conventional road cars. Dual-clutch transmissions use two fundamentally different types of clutches: either two wet multiplate clutches, bathed in oil (for cooling), or two dry single-plate clutches. The wet clutch design is generally used for higher torque engines that can generate 350 newton metres and more (the wet multiplate clutch DCT in the Bugatti Veyron is designed to cope with 1,250 Nm), whereas the dry-clutch design is generally suitable for smaller vehicles with lower torque outputs up to 250 Nm. However, while the dry-clutch variants may be limited in torque compared to their wet-clutch counterparts, the dry-clutch versions offer an increase in fuel efficiency, due to the lack of pumping losses of the transmission fluid in the clutch housing. Currently, three variations of clutch installation are used. The original design used a concentric arrangement, where both clutches shared the same plane when viewed perpendicularly from the transmission input shaft, along the same centre line as the engine crankshaft; when viewed head-on along the length of the input shaft, this makes one clutch noticeably larger than the other. The second implementation uses two single-plate dry clutches ? side-by-side from the perpendicular view, but again sharing the centre line of the crankshaft. A later variation uses two separate but identically sized clutches. These are arranged side-by-side when viewed head-on (along the length of the input shaft and crankshaft centre line), and also share the same plane when viewed perpendicularly. This latter clutch arrangement (unlike the other two variations) is driven by a gear from the engine crankshaft.