Taking your R107 to the next level with LSD.

Those of you who are familiar with SportLine will know precisely what we’ve done to transform the R107 into a road-dominating performance-focused SL. We have honed a series of different improvements focused on getting the most out of the R107 SL’s sturdy structure, range of engines and unique style. In our last focus article, we looked at anti-roll bars in which we incorporated Proud Owner, Nigel Thomas’ feedback on how this upgrade improved the driving experience of his 300SL.
This piece focuses on LSD (no not the hallucinogenic kind), how it works and why you should consider this upgrade for your 300SL.

What is LSD or Limited Slip Differential?

In a nutshell, LSD helps effectively distribute the power produced by your engine through to your wheels, converting this into rotational energy to propel your vehicle effectively. LSD puts the power to the road in a way that favours improved performance and handling.

Where does slip come in?

The engineering of this type of differential focused specifically on reducing wheelspin when power is applied, and the wheels are most likely to slip. This is achieved by redistributing the power from the wheel displaying signs of slippage, moving it to the wheel with the most traction. This is achieved either by an electronic configuration, mechanical system or both. It is suggested, however, that a mechanical system is more efficient and reliable than an electronic system using wheel speed sensors.

How does it work?

To understand how it works, let’s consider the most common type of differential – the Open Differential. These are generally found on the early R107 models such as the 280SL, 350SL, 380SL and 450SL, as well as the 300SL which was offered in the mid-1980s. An open differential uses gears to put power to the wheels with the least resistance, and can sometimes mean the tires with the least resistance. This can cause problems when driving high-powered vehicles, as all that torque will end up spinning both wheels.

The LSD Experience:

Later V8 models such as the 420SL, 500SL and 560SL were offered with a Limited Slip Differential, while the 300SL did not receive this option until we introduced SportLine. We utilise a Quaife ATB (Automatic Torque Bias) LSD that is made up of a complex array of gears that pulsate power between the left and right side of the axle, allowing power to be sent to the wheel with the most grip. Where the Grippa differentials found on the V8s lock both wheels when a certain amount of torque is applied (making the 560SL particularly tail-happy), the Quaife ATB we use doesn’t lock both wheels.
This gives just the right amount of flexibility in the rear end to improve traction but also offers a little rear axle freedom when desired.

Why Quaife ATB?

There are a number of different types of LSD available on the market and we have selected Quaife due to its durability and composition. Unlike plate-LSD systems, Quaife ATB is absent of springs, ramps and other components that require regular service intervals, making the Quaife ATB much more reliable. Its helical gears are extremely reliable and produced to accept standard transmission oils.

How does it affect an R107’s handling?

For rear-wheel drive vehicles such as the R107 300SL, an LSD will greatly reduce oversteer and enable more control in these circumstances, offering a more exciting and rapid drive.

For this particular article, we felt it was only right to showcase how it works in the form of a video. How often do you see a 450SL doing doughnuts? Never really… Enjoy this short clip of Jake making the most of Matilda’s Limited Slip Differential.

Should you fit a limited slip differential to your R107?

Where the purists might not agree that altering the originality of their R107 for the better goes against the principles of classic car preservation, we believe that you only live once and an LSD is going to be just another step further to improving the driving experience.

Gains from a Limited Slip Differential are obvious – they improve traction when cornering and combine this with other improvements such as an anti-roll bar, adjustable shocks and dampers, and you have a recipe for a sharp and engaging R107. Those early V8s would also benefit from this upgrade, particularly as these V8s make the perfect contenders for endurance rallies.

Will it affect the value of your R107?

Ultimately, you have improved your R107 for the better. An LSD improves will add confidence to the driver, allowing them to engage in more spirited driving and have a little fun. With the investment made in an LSD, it is only going to add value and appeal to your R107.

Stand out from the crowd and improve your R107. Start with an LSD and let the trip take you further on your SportLine Journey.