Arlan Motorsport - Suspension Systems

Suspension Systems

The suspension system provides a number of important functions to improve cornering speeds, car control under braking, and under acceleration exiting a corner. You can't expect the best braking unless the suspension is doing its job. Your corner speed might be determined greatly by the grip of the tires, but you can't get the most from your tires if the suspension isn't working properly. Nor can you expect to get power to the road (traction) if the suspension isn't doing its job. The suspension is in short - the single most important aspect of car setup.

Springs provide the primary support of weight on each corner of the car. The exact spring rate however is a much more complex issue.

Shocks (or more properly spring dampers) besides controlling the oscillations of the springs, also control vehicle dynamics when braking into a corner, turning on corner entry, and when trying to get traction exiting a corner.

Stabilizer bars control weight transfer during cornering and resist body roll. Adjustment of the stabilizer bars is made to balance the handling (mechanical grip) of the car particularly in mid corner on low to medium speed corners.

Suspension bushings are often replaced to help with alignment stability or the ability to predict how accuratly the suspension will maintain setup.

Aero dynamics finally are used to provide down force at the front and rear to improve cornering at high vehicle speeds. The need to keep air from entering under the chassis is critical to prevent lift, and closing off the under body, using front splitters, adding a rear diffuser to help get any air that does find its way under the car to exit as quickly as possible, and finally a rear spoiler or better yet a wing that will provide down force while reducing the aerodynamic drag of a simple spoiler. Aerodynamic devices interact with the suspension, so they become one of the factors in determining among other things spring rates and ride height.

Why you can't just pick a few components, bolt them together and expect your suspension to work.

The process of determining the exact components and their design has been tackled by a variety of companies over the years with varying degrees of success.

In some cases such as development of springs, stabilizer bars, suspension bushings and similar hardware where the engineering and manufacturing process is straight forward, it is usually just required to select a supplier or suppliers that really know what the're doing. Those that do, have tended to rise to the surface as original equipment manufactures. If they also manufacture an aftermarket or performance line then they are a good candidate as a supplier.

The small aftermarket suppliers have been far more suspect. Either they don't have the real engineering training and experience to develop the components in the first place, (and that has nothing to do with their company size) or they don't have the financial backing to properly design, test, manufacture, package and promote their products.

"Bolt-on" - The biggest joke in the aftermarket ...

The number of aftermarket companies with improperly designed components is staggering. Beyond proper use of materials, designs that actually support the stress applied to the component, and proper use of correct strength hardware, the vast majority of aftermarket products don't even fit the application they were designed for without modification, replacement of hardware, or partial or complete redesign to fix faulty and sometimes dangerous issues.

Qualified products through development and testing.

Product development is expensive whether you are the manufacturer, or the one doing chassis setup. The result is a process of locating good quality products that are already available, and then determining if any further development or refinement is required. We often work with these suppliers to help them refine their products. If none is available, then and only then we do a ground up design and manufacturing process.

A Total Solution

After all of the development above, we use our years of experience to recommend a "total solution" that takes into consideration:

Intended use of the vehicle

Tires (type and construction) that will be used - to determine component selection

Component availability - what's ready to go

Series if for competition use (series rules)

Customer expectations integrated into the solution