For decades, suspension tuning was a matter of compromise. The components and settings that delivered the best ride quality also returned sloppy handling as cornering forces got higher. Conversely, the setup that delivered the best handling usually delivered a harsh ride on all but glass-smooth pavement.
Thus, suspension setup has generally been a crapshoot, with manufacturers typically erring on the side of comfort and caution. Recent developments, such as Delphi’s magnetorheological dampers (available on the Chevy Corvette, the Cadillac ATS and the Ferrari 458 Italia to name just a few examples) have done much to balance ride and handling.
Delphi’s system works by changing the viscosity of the damping oil, which contains minute iron particles. Magnetize the particles, and the suspension gets very stiff; lower the electromagnetic charge, and the suspension becomes more compliant and comfortable.
Another way to accomplish the same thing is by increasing the hydraulic pressure within the dampers, which is exactly what Mercedes-Benz does with its Active Body Control (ABC) suspension. Relying on five sensors to detect body motion (side to side, front to back or up and down) the ABC system increases or decreases damper pressure based on conditions.
In addition to the five main sensors, there are sensors embedded into each damper to measure position and (presumably) hydraulic pressure. A high-pressure pump can vary the setting of each damper in as little as 10 milliseconds, dialing in the exact ride quality that the driver expects under a wide variety of conditions.
Are there downsides? Complexity and expense come to mind, and when such a system develops problems, there’s little chance that a local mechanic will be able to troubleshoot and repair them. While there’s no longer need to upgrade dampers for better performance, there’s no possibly of replacing a worn component on your own, either.
What’s your take on systems like Mercedes-Benz’s ABC? Do they represent progress, or are the gains not worth the inevitable added costs? Would such a system encourage you to buy a particular model, or keep you from doing so?