Although it may be impossible to tell from the exterior, there are several components on a vehicle that makes it essential for it to move in a sporty fashion. One of these components is the limited slip differential (LSD). The primary reasoning is that the LSD helps put more power to the ground when the gas pedal is depressed. The linear relation of the gas pedal and forward vehicle movement becomes more clear which gives the driver more confidence and assurance. Once the LSD's mechanism and effectiveness is realized, it will surely be claimed by all that this component is crucial to performance driving. We decided to test this essential component in our FR vehicle!

A LSD is a component that once installed, prevents that power loss. When the vehicle makes a turn, the LSD prevents the inner wheel from spinning and makes both wheels turn at the same revolution. Not only does it do this, but it also firmly plants both tires to the ground for improved traction. The vehicle moves forward at a faster and safer rate.	On most sports cars, there are helical LSD systems that already come previously equipped by the manufacturer. These LSDs are often considered to be too weak and fail to produce any effective results. In order to fully enjoy the sportiness of the vehicle an aftermarket LSD is highly recommended to increase the throttle response.
This is a car performing doughnuts with a stock differential. Take a look at the left rear wheel. Since the stock LSD is too weak to lock both wheels, the power escapes by letting the inner wheel spin freely. Even if the throttle is depressed further at this point, more power would just escape by spinning the free wheel. The difference is especially noticed in the minute amount of tire smoke that is displayed. Take a look at the rear wheels. The powerful LSD system which evenly locks up the left and right wheels firmly and effectively places the power to the pavement. Smoke is evident from both wheels as well. Since the full engine power is efficiently utilized, one can expect a greater forward movement of the car.

Basically, the LSD is engaged when it senses a difference between left and right rear wheel revolutions in the driveline. It is not working when the vehicle is going straight. When the LSD becomes engaged, the left and right wheels are spinning at an equal rate, so if one wheel is about to spin freely, it eliminates that action. Modern LSD systems such as the Cusco Type-RS is very smooth during normal driving.	It can hardly be felt when driving in the parking lot or street driving. In fact, it can be said that during normal driving, it feels very close to a stock differential. It distinguishes itself when the vehicle is put into a drift and one wheel attempts to spin faster than the other from hard acceleration.
When a vehicle goes into a turn, the inner wheel attempts to spin freely due to less weight load on the wheel. All the power becomes centralized here, and the wheel just keeps spinning freely. The result is that the vehicle loses power as it tries to move forward. When an LSD system is installed, the moment the inner wheel attempts to spin freely, the LSD "locks" and spins the other wheel at the same rate. The result is the power is maximized to the pavement and the vehicle moves forward at a higher velocity. When the LSD senses a difference of revolutions between the left and right wheels, the cross shaft (RED) pushes the cam (GREEN), spreading the pressure ring (BLUE) outward. This causes friction in the clutch plates (WHITE), locking both the left and right wheel. This is how a LSD is able to evenly distribute wheel revolution to the drivetrain.

Let's perform a comparison test between the stock differential and an LSD equipped rear end by doing doughnuts, slalom runs, and tight turns.   During a doughnut maneuver, precise control of the throttle is necessary. If the drivetrain reacts accordingly, it should be easy to continue the doughnut circle.   During a slalom run, the driver will press and let off the throttle repeatedly to adjust to the vehicle movement. If the drivetrain is working accordingly, the vehicle should display sharp and quick movements.	When performing the tight turn, the brakes are engaged when the vehicle approaches the turn. Then the throttle is depressed to move the vehicle forward. On rear wheel drive vehicles, the LSD enables stability when the brakes are violently engaged, so a sudden decrease in speed can be safely performed. The throttle can be pressed to move the forward at a faster rate with the LSD as well.

	Sumiyama is involved in the Cusco R&D department, and also is the winner of the Japanese Rally race. He is going to provide us his professional opinion. This lovely lady is involved in most of the Kanto area drift events, and will provide us a full report of an LSD installed vehicle.

Beginners may think that an LSD may not be advantageous to their performance but that is not the case.   Beginners should be able to feel the increase in forward movement as soon as the throttle is hit after a turn.   With an LSD, the vehicle becomes more stable and controllable, making it safer. This will decrease lap times, no matter what skill level you are.	Once an enthusiast gains more driving skill, they will be able to switch the direction by the car with the throttle, and do longer and more stable drifts. An LSD is an absolutely essential item from beginners to professionals when there is aggressive driving involved. We would urge you to try it out, to experience first hand the difference between it and a stock differential.

With the LSD installed, the rear left and right wheels lock up according to throttle play. The result is that the vehicle is easier to control Similar to doing doughnuts, the more the LSD works, the more the vehicle is able to move forward. The result is a faster vehicle. The LSD can be felt from the braking before entry all the way through exiting the turn. The LSD provides a stable ride and helps exhibit a more intense performance. Without an LSD, when the vehicle is launched so the wheels lose traction, one wheel ends up spinning harder. The LSD provides traction to distribute evenly to both wheels, enabling a rocket like launch.

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Contact: Carrosser 027-352-3578 (Japan)