Suspension
Important: The following information is based on personal assessments and experiences and has been compiled to the best of our knowledge and belief. We do not guarantee the accuracy of the information.
The basic design of the W202 suspension clearly stands out from other vehicles of similar years. The design with double wishbones on the front axle and a multi-link axle on the rear axle, which also has the same arrangement of struts as a double wishbone, was an absolute innovation in this vehicle category at the time. Even today, the double wishbone design is still the first choice for modern racing vehicles. Of course, the suspension of the W202 was deliberately designed to be comfortable at the time, but the basic design offers extreme motorsport potential, given you make the right adjustments.
The following lists the adjustment possibilities and explains which measures make sense:
Springs:
The arrangement of the springs is actually not optimal for one reason only. As soon as you want to use the spring rates to achieve values that are necessary for a motorsport setup, the springs automatically become very heavy and massive due to the unfavorable lever on the wishbone. In addition, special designs are necessary for height-adjustable chassis, as the adjustment cannot be arranged on the damper as in many other vehicles.
Regardless of these two negative aspects, there is nothing in the arrangement of the springs that speaks against their suitability for motorsports use. The only difficulty lies in the technical implementation of spring rates that are high enough.
All springs and suspensions currently available on the market for the W202 do not meet the requirements for motorsport or track tool use. In addition, the ratio of the spring rates between the front axle and rear axle is often unbalanced. Spring manufacturers often refer to the permissible axle load, which for the W202 can be 970-1010kg on the front axle and 1040-1150kg on the rear axle, depending on the year and model. These maximum values are often used to determine the spring rates. In the end, this means that in normal driving conditions (1-2 people, half-full tank, little luggage) the spring at the rear is too hard or, conversely, too soft at the front.
Depending on the engine and equipment, the W202 has a weight distribution of 53-56% on the front axle and 44-47% on the rear axle during normal driving. With a neutral suspension design, the ratio of the spring rates between the front and rear would also have to be the same (of course, this only applies to standardized spring rates, i.e. when the influence of different lever lengths of the wishbones has been excluded from the calculation).
We were able to find out the following through extensive research into the well-known suspension and spring manufacturers for the W202:
- Eibach: The design of the front axle to the rear axle is based on normal driving conditions; the spring rates of the hardest lowering springs correspond to approximately 0.3x the spring rate of a motorsport-like spring on the front and rear axle.
- H&R: The design of the front axle to the rear axle is based on the maximum axle load; the spring rates of the hardest lowering springs correspond to approx. 0.25x the spring rate of a motorsport-style spring on the front axle and approx. 0.3x on the rear axle.
- KW (incl. V2): Front axle to rear axle design is based on the maximum axle load; spring rates of the hardest lowering springs correspond to approx. 0.33x the spring rate of a motorsport-like spring on the front axle and approx. 0.4x on the rear axle.
- Vogtland: The design of the front axle to the rear axle is based on the maximum axle load; the spring rates of the hardest lowering springs correspond to approx. 0.27x the spring rate of a motorsport-style spring on the front axle and approx. 0.33x on the rear axle.
- FK (thread): The design of the front axle to the rear axle is based on normal driving conditions; the spring rates of the hardest lowering springs correspond to approx. 0.44x the spring rate of a motorsport-like spring on the front axle and approx. 0.4x on the rear axle.
Since the market unfortunately does not offer any better options at a reasonable price, we have launched our TrackPro spring set (Eibach / Fundametrik). This offers motorsport spring rates taking into account a practical weight distribution of V54%/H46% for the light engines and V56%/H44% for the heavy engines.
Dampers/Shocks:
Spring and damper should really only be viewed as a unit. For a motorsport driving experience, it is important that the spring rates are high enough, but you also need a damper that matches these spring rates. As shown above, there have been no reasonable spring options for a motorsport W202 to date, so there are hardly any affordable damper options for the corresponding spring rates.
For this reason, we have launched our TrackPro damper set at the same time as the springs, which is optimally matched to the spring rates of the TrackPro spring set.
Understandably, not everyone wants to drive with a suspension that is similar to a motorsport suspension in everyday life, which is why we also offer the TrackLight shock absorber set. This can be optimally combined with, for example, standard Eibach lowering springs and differs from other sports shock absorbers on the market in particular due to its increased compression rate. The compression rate has a decisive influence on whether a firm suspension still feels comfortable.
Shock absorbers are often only adjustable in the rebound rate, which is usually sufficient if the compression rate is optimally designed for the spring rate. If the compression rate is too weak, the tendency is to set the rebound rate accordingly tight, which leads to an unbalanced relationship between the two stages and makes the vehicle firm but at the same time unpleasantly "bumpy". In the worst case, the car can easily lose contact with the road, as the compression stage allows for a relatively rapid compression, while the rebound stage delays the rebound relatively significantly.
Caster or caster angle:
Roughly explained, the caster angle refers to the inclined position of the steering rotation axis on the wheel carrier in the direction of travel, which creates a certain caster distance. Caster has two desired effects in passenger cars, namely on the one hand it generates a restoring torque on the steering axle to enable stable straight-line driving and on the other hand it changes the camber when turning. On the outside wheel, the camber goes more into the negative area, with the wheel on the inside of the curve more into the positive. As a result, the wheels "push" themselves into the curve even more, which enables increased cornering speeds.
However, a high caster generates high steering forces, which is why car manufacturers have to find a compromise between an ideal caster value for maximum performance and the still reasonable steering forces for the driver.
In the W202, this value is logically very comfort-oriented. The driver should also be able to steer very easily and with even resistance during turning and parking manoeuvres. In practice and also in the technical literature, the caster angle of the W202 is about 4-5° on the front axle. A value that is far too low for a performance-oriented vehicle.
When Mercedes wanted to establish a sporty image in the coming generations, the caster angle, for example, was also significantly adjusted. With the W203 and W204, the caster angle is already 9-11° on the front axle.
Roughly simplified, you can say that every additional degree of caster on the front axle helps the W202 to move more sportily.
The caster on the W202 is only adjustable to a limited extent and not entirely independent of the camber. Corresponding camber correction screws allow different positions of the bearings of the lower wishbone, which allows camber and caster to be adjusted in theory, even if only in 2-3 steps. However, since we are also looking for more camber (or more negative camber), this adjustment option for the caster is out.
With our Uniball bearing set for the front axle, we wanted to solve this problem, so the bearing unit for the upper control arm on the front axle has spacers that can be used to change the position of the control arm in the direction of travel. An upper control arm that is moved further back, results in a greater inclination of the steering rotation axis and thus a higher caster angle. With our Uniball bearing set, up to 3° more caster can be achieved on the front axle and thus a total value of up to 8° can be achieved.
Roughly explained, the caster angle refers to the inclined position of the steering rotation axis on the wheel carrier in the direction of travel, which creates a certain caster distance. Caster has two desired effects in passenger cars, namely on the one hand it generates a restoring torque on the steering axle to enable stable straight-line driving and on the other hand it changes the camber when turning. On the outside wheel, the camber goes more into the negative area, with the wheel on the inside of the curve more into the positive. As a result, the wheels "push" themselves into the curve even more, which enables increased cornering speeds.
However, a high caster generates high steering forces, which is why car manufacturers have to find a compromise between an ideal caster value for maximum performance and the still reasonable steering forces for the driver.
In the W202, this value is logically very comfort-oriented. The driver should also be able to steer very easily and with even resistance during turning and parking manoeuvres. In practice and also in the technical literature, the caster angle of the W202 is about 4-5° on the front axle. A value that is far too low for a performance-oriented vehicle.
When Mercedes wanted to establish a sporty image in the coming generations, the caster angle, for example, was also significantly adjusted. With the W203 and W204, the caster angle is already 9-11° on the front axle.
Roughly simplified, you can say that every additional degree of caster on the front axle helps the W202 to move more sportily.
The caster on the W202 is only adjustable to a limited extent and not entirely independent of the camber. Corresponding camber correction screws allow different positions of the bearings of the lower wishbone, which allows camber and caster to be adjusted in theory, even if only in 2-3 steps. However, since we are also looking for more camber (or more negative camber), this adjustment option for the caster is out.
With our Uniball bearing set for the front axle, we wanted to solve this problem, so the bearing unit for the upper control arm on the front axle has spacers that can be used to change the position of the control arm in the direction of travel. An upper control arm that is moved further back, results in a greater inclination of the steering rotation axis and thus a higher caster angle. With our Uniball bearing set, up to 3° more caster can be achieved on the front axle and thus a total value of up to 8° can be achieved.
Camber:
The camber or camber angle is already a familiar quantity to many. It refers to the inclination of the wheels towards or away from the vehicle. The camber thus plays a decisive role in determining the bearing profile of the tyres, as it determines where the highest load is on the tread (inside, middle, outside) when driving straight ahead or cornering. Since an everyday car, in contrast to a circuit vehicle, almost only sees straight roads and usually does not drive through curves near the limit, the manufacturer provides a fairly neutral camber setting.
However, the more suitable a vehicle is for the racetrack, the more important a sport-oriented camber setting becomes. Unfortunately, the camber of the W202 can only be adjusted to a limited extent on the front axle and not at all on the rear axle, but in principle this is not so bad, as the following explanations should show.
Front axle: As mentioned above, there are camber correction screws that can be used to change the position of the bearings of the lower control arm. Ideally, this should bring both bearings of one side to the outside as far as possible. This already allows a fairly good negative camber angle to be achieved on the front axle. The camber angle is a dynamic variable and changes due to the effect of cornering forces on the chassis. On the one hand, the freedom of movement in the original rubber bushings allows the camber angle to be changed, but on the other hand, the roll angle, or in other words, the angle at which the vehicle leans towards the outside of the curve, eliminates the desired effect of the camber angle.
In order to ensure the desired effect of the camber angle, supporting measures can be taken, such as a hard bearing of the wishbones, which does not allow any unwanted displacements due to cornering forces, and a correspondingly firm suspension and stabilizer to reduce the vehicle's tendency to roll.
The former can be achieved with our Uniball bearing set for the front axle, the second with the use of our Fundametrik TrackPro suspension, the advantages of which we have already explained above.
With these measures and a performance-oriented ride height, the front axle is also well equipped for race track use and is in the green zone in terms of camber angle.
Rear axle: The aftermarket offers adjustable camber struts for the rear axle. Unfortunately, the devastating disadvantage of these struts is that they also change the caster angle on the rear axle. On a rear axle, the existence of a caster angle is often not mentioned, as the kinematics are ideally considered to be completely rigid and therefore no instabilities can occur. But here, too, the original rubber mounts leave enough room for movement to make an unfavourable caster noticeable. The scenario is often the following: Too much lowering results in too negative a camber on the rear axle. With the help of an adjustable camber strut, the wheels are then brought back to a slightly more neutral position. The caster changes so unfavorably that the car feels as if the rear axle is floating when accelerating. For this reason, we strongly advise against the use of adjustable camber struts.
In practice, the camber angle on the rear axle is in the green zone at a performance-oriented height. Problems therefore only occur if the car is too low. Our Uniball bearing set can also be installed here to ensure the highest level of precision and stability on the rear axle.
However, the more suitable a vehicle is for the racetrack, the more important a sport-oriented camber setting becomes. Unfortunately, the camber of the W202 can only be adjusted to a limited extent on the front axle and not at all on the rear axle, but in principle this is not so bad, as the following explanations should show.
Front axle: As mentioned above, there are camber correction screws that can be used to change the position of the bearings of the lower control arm. Ideally, this should bring both bearings of one side to the outside as far as possible. This already allows a fairly good negative camber angle to be achieved on the front axle. The camber angle is a dynamic variable and changes due to the effect of cornering forces on the chassis. On the one hand, the freedom of movement in the original rubber bushings allows the camber angle to be changed, but on the other hand, the roll angle, or in other words, the angle at which the vehicle leans towards the outside of the curve, eliminates the desired effect of the camber angle.
In order to ensure the desired effect of the camber angle, supporting measures can be taken, such as a hard bearing of the wishbones, which does not allow any unwanted displacements due to cornering forces, and a correspondingly firm suspension and stabilizer to reduce the vehicle's tendency to roll.
The former can be achieved with our Uniball bearing set for the front axle, the second with the use of our Fundametrik TrackPro suspension, the advantages of which we have already explained above.
With these measures and a performance-oriented ride height, the front axle is also well equipped for race track use and is in the green zone in terms of camber angle.
Rear axle: The aftermarket offers adjustable camber struts for the rear axle. Unfortunately, the devastating disadvantage of these struts is that they also change the caster angle on the rear axle. On a rear axle, the existence of a caster angle is often not mentioned, as the kinematics are ideally considered to be completely rigid and therefore no instabilities can occur. But here, too, the original rubber mounts leave enough room for movement to make an unfavourable caster noticeable. The scenario is often the following: Too much lowering results in too negative a camber on the rear axle. With the help of an adjustable camber strut, the wheels are then brought back to a slightly more neutral position. The caster changes so unfavorably that the car feels as if the rear axle is floating when accelerating. For this reason, we strongly advise against the use of adjustable camber struts.
In practice, the camber angle on the rear axle is in the green zone at a performance-oriented height. Problems therefore only occur if the car is too low. Our Uniball bearing set can also be installed here to ensure the highest level of precision and stability on the rear axle.
Topic vehicle height:
Anti-roll bars:
As previously mentioned, the effectiveness of the anti-roll bar changes with the vehicle’s ride height and the resulting angle of the control arms and links. However, since the current market offers only limited options for differently rated anti-roll bars—aside from OEM variants and the H&R sway bar kit (which mirrors the sport model specifications)—a deeper technical exploration of this topic offers limited practical value at this time.
For a sportier driving experience, it is generally worthwhile to upgrade to the thickest available option. For four-cylinder models, this means a 26 mm bar on the front axle; for five- to eight-cylinder models, 28 mm front and 18 mm rear. Only the C43 and CLK55 came with a thicker 30 mm front anti-roll bar, which is no longer available from Mercedes.
Suspension bushings:
Suspension bushings are also a key consideration when aiming for a more dynamic or motorsport-oriented setup. From the factory, the mounting points for suspension arms and axles are designed with comfort and cost-efficiency in mind. Uniball bearings—like those included in our front and rear Uniball bearing kit—as well as rigid motorsport subframe bushings, significantly improve steering precision and vehicle responsiveness.
There are often concerns that switching to rigid bushings will compromise everyday drivability due to increased noise. However, based on our experience, we can confidently say that this is not the case: when using Uniball bearings and solid rear subframe mounts, we have not observed any significant or disturbing increase in noise.