Modern engines can be driven at extremely low rpms. The trend is toward ever increasing engine torques. Wind-tunnel-optimized bodies are creating less wind noise. New calculation methods are helping reduce vehicle weights and weight-saving concepts are boosting engine efficiency as well. The addition of a fifth or a sixth gear can also reduce fuel consumption. Thinner oils are making precise shifting easier. In short: The sources of noise are increasing and natural damping is decreasing. What has remained is the principle of the internal combustion engine whose cyclical combustion processes excite torsional vibrations in the drive train – the unpleasant consequences of which are gear rattles and body booms.
Drivers who are accustomed to increased comfort no longer accept such background noises. The job of the clutch is now more important than ever – in addition to engaging and disengaging, it must effectively insulate the engine’s vibrations. Physically, this is easy to solve: The mass moment of inertia of the transmission must be increased without increasing the mass to be shifted. This dampens the engine’s torsional vibrations and brings about the desired comfort level. The process reduces load on the transmission at the same time.
It's all in the name
LuK was the first manufacturer in Europe to develop and sell a dual-mass flywheel in large-scale standard production that was able to realize this physical principle. The name says it all: The mass of the conventional flywheel was simply split in two. One part continues to belong to the engine’s mass moment of inertia, while the other part now increases the mass moment of inertia of the transmission. The two decoupled masses are linked by a spring/damping system. One clutch disc, without a torsion damper, between the secondary mass and the transmission handles the engaging and disengaging functions. A favorable side effect is that the transmission is easier to shift because of the low mass to be synchronized, and there is less synchronization wear.
LuK astia se lauda cu inlocuire doar pentru unele volante cu masa dubla, poti pune o lista te rog? E si Z13DT in lista?
Uite si ce face chip-tuningul, tot de la amicii astia Luk:
Chip tuning is a quick, easy and fairly inexpensive way of increasing engine power output. For a relatively small amount of money you can easily increase the power of an engine by up to 30%. Facts not normally considered are whether the engine is durable enough to withstand the higher outputs, e.g. thermal overloading, and also if the rest of the drive train can withstand the increase in torque/performance. Usually the torsion damper system of a Dual-Mass Flywheel, just like the remaining parts of the drive train, is designed for the engine for which it is intended. In many cases the safety reserve of the Dual-Mass Flywheel is used up or exceeded by a torque increase, sometimes by more than 30%. As a consequence, the arc springs can already be completely compressed during normal driving, which deteriorates noise insulation and can cause the vehicle to jolt. As this is the case at half of the firing frequency, very high loads are quickly produced and transferred not only to the Dual-Mass Flywheel, but also to the transmission, which could result in damage to drive shafts and the differential. Damage can range from increased wear to a catastrophic failure resulting in a huge repair bill. The operating point of the Dual-Mass Flywheel is shifted towards its security reserve by the increase in the power of the engine. During driving, the Dual-Mass Flywheel is permanently overloaded by the higher engine torques. This causes the damper springs in the Dual-Mass Flywheel to operate “fully loaded” more often than they are designed to and can destroy the Dual-Mass Flywheel! It is true that many tuners give a warranty on the vehicle when increasing power output. But what about when
the warranty period is over? The increase in output can damage other components in the drive train slowly but continuously. Sometimes these components will fail at a later date (after expiration of any warranty given!), which means the repair costs have to be paid by the customer.
Happy tuning!