EKaru

When I drive my wife's S4, I notice that the car is very bouncy or jiggly over the pavement, but it's not harsh.... On the other hand the C55 doesn't exhibit the bouncy ride, but the ride is very harsh over the bumps.. How does that work?
Eric....

05C55

The manufacturers try to find a happy medium between good handling and ride quality, both of these cars essentially looking to do similar things, they use a combination of spring rate and the dampening/compression/rebound rates of the shocks or struts and anti-sway bars to accomplish this. In my opinion, Audi springs the S4 a bit softer and uses more aggressive shock/strut tuning, sway bars and geometry to offer what is arguably as good if not better handling than the C55 while offering a slightly more compliant ride. This is my guess because I'm not sure, its only how I personally think the car feels and this is based on limited seat time. My hang up with the Audi is that softer more compliant ride, even though it may handle better overall makes me think it is less aggressive and less sporty. One of the main reasons I opted for the C55. My money would bet that a slightly more aggressive spring set on the Audi would make it feel a lot closer to the C55 but I assume you are just asking out of curiosity. I'm no suspension guru and its pretty complicated but the srping rate and the shock tuning are the two primary pieces of that puzzle.

neoprufrok

Somebody correct me if I am wrong - but I my understanding is that the S4 uses progressive springs which allow for some compliance and then stiffens up considerably. I've been told that the C55 uses linear springs or a less progressive setup than the S4. Also as 05c55 said, they use pretty aggressive shock/struts. I actually prefer the C55 handling over the S4 handling - but that's mainly because the AWD S4 seems a little heavier or more likely to push through the corners than the C55.

PUREMS

One of the big differences between these two cars is the shock. AMG uses Bilstein technology which tends to be on the firm side when hitting rougher roads. The Audi uses a shock from Sachs-Boge (and Monroe), which is a twin tube design. This tends to be a bit more comfortable on the rougher roads.

smgC32

Could someone please confirm if the new C55 has a Bilstein stamp on its strut and shock bodies? Sachs has been supplying the struts and shocks for the AMG C32 and believe they also are the supplier for the C55.

Bilstein's in general are smoother in their gradiant adjustments between bump and rebound than twin tube designs. Mitsu changed over to the Bilstein monotube design on the new MR, which is more compliant on the street and faster at the track.

Compliance on the street is a matter of low speed vs. high speed tuning of the dampers.

Harris

Ask Neal, he has his shocks taken out, he should know what it is.

05C55

The springs are Eibach but I cannot recall what type of shock is used.

BlackC230Coupe

The C55 shocks or struts do not say Bilstein on them. It said something, i will have to check to see what it was, i just didn't pay much attention to them off the car. If anyone wants, i can take pics of the springs/shocks.

cntlaw

C55 suspension is truly harsh on bumps especially rear wheels but believe me this is where we get the crawling feel of the car which to me is perfect for high speed.