## Sunday, March 12, 2023

The word Torsen certainly means something to you, we generally talk about it to characterize the famous limited slip differentials intended for tractions with a very powerful engine. Indeed, the latter then find it difficult to pass all the power with a classic differential, in this case there is general panic and each wheel begins to turn at its own pace in the most total disorganization (a wheel which does not not move forward while the other skates / burns "wildly"). In short, it is then necessary to be able to put a little coherence in all this by limiting the speed delta between the wheels, so here is an example of the usefulness of the Torsen.

Let's first see the general principle of this type of gear knowing that the name comes from the contraction between the words Torque and Sensing.

A conventional differential makes it possible to distribute power from a single source between the two axles: in this case the power of the engine is distributed over two wheels. It allows, in addition to distribute the power on two axes and that the torque can be different on each axis. For example, with a standard differential, if I have one of the wheels in a vacuum (which therefore undergoes no resistance), all the torque will be sent to the other. This type of differential is basic and therefore reacts in a "primary" way. In my example, we will therefore have a car which sees its wheel in a vacuum turn while the other does not move... The car therefore remains in place and cannot move forward.

With a Torsen, we have exactly the same thing except that the gear which composes it prevents that the speed of rotation between the axles / axes is too high. As a result, we cannot end up with one wheel spinning in a vacuum alone while the other does not move. If one of the wheels moves, the other will also have to do the same! Of course we are not talking about a differential lock here, it is still possible to rotate the wheels at a different speed but up to a certain limit: slippage is therefore limited between the two axles.

Note therefore that the Torsen brings a permanent link between the two axes / axles, the limited slip cannot be controlled and it is parameterized according to the gears which will be used (some Audi QUattro are in 50/50 and others, the RS generally, are in 40/60 to have a propulsion effect).

This is therefore (among other things) for very powerful tractions which will then no longer have a single wheel that turns by itself when you accelerate like a racing driver. Indeed, with a classic differential the car will have its two desynchronized front wheels which will turn independently at the speed they want (depending on the degree of grip on each axle). The front axle then plays it rodeo and does a bit of a mess, it is then necessary to relieve the engine load to get back on track.

The word Torsen certainly means something to you, we generally talk about it to characterize the famous limited slip differentials intended for tractions with a very powerful engine. Indeed, the latter then find it difficult to pass all the power with a classic differential, in this case there is general panic and each wheel begins to turn at its own pace in the most total disorganization (a wheel which does not not move forward while the other skates / burns "wildly"). In short, it is then necessary to be able to put a little coherence in all this by limiting the speed delta between the wheels, so here is an example of the usefulness of the Torsen.

Let's first see the general principle of this type of gear knowing that the name comes from the contraction between the words Torque and Sensing.

A conventional differential makes it possible to distribute power from a single source between the two axles: in this case the power of the engine is distributed over two wheels. It allows, in addition to distribute the power on two axes and that the torque can be different on each axis. For example, with a standard differential, if I have one of the wheels in a vacuum (which therefore undergoes no resistance), all the torque will be sent to the other. This type of differential is basic and therefore reacts in a "primary" way. In my example, we will therefore have a car which sees its wheel in a vacuum turn while the other does not move... The car therefore remains in place and cannot move forward.

With a Torsen, we have exactly the same thing except that the gear which composes it prevents that the speed of rotation between the axles / axes is too high. As a result, we cannot end up with one wheel spinning in a vacuum alone while the other does not move. If one of the wheels moves, the other will also have to do the same! Of course we are not talking about a differential lock here, it is still possible to rotate the wheels at a different speed but up to a certain limit: slippage is therefore limited between the two axles.

Note therefore that the Torsen brings a permanent link between the two axes / axles, the limited slip cannot be controlled and it is parameterized according to the gears which will be used (some Audi QUattro are in 50/50 and others, the RS generally, are in 40/60 to have a propulsion effect).

This is therefore (among other things) for very powerful tractions which will then no longer have a single wheel that turns by itself when you accelerate like a racing driver. Indeed, with a classic differential the car will have its two desynchronized front wheels which will turn independently at the speed they want (depending on the degree of grip on each axle). The front axle then plays it rodeo and does a bit of a mess, it is then necessary to relieve the engine load to get back on track.