Camber 101 - December 2007 Wrenchin'
photographer: Marcus DI Sabella
There is hardly a single vehicular enhancement that is more commonplace than lowering the car's ride height. Whether it be for looks or handling, we're convinced that removing an inch or two (or even three) of ground clearance is synonymous with Honda Tuning. Over the years, there have been many developments that are designed for the specific demands of low-riding tuners. Short case dampers, skid plates and higher spring rates are all designed to help keep suspension compliant and handling in check by way of resisting the bottoming of the car or the dampers.
Suspension modification is very common today, but one should be careful not to oversimplify the suspension system's dynamics. It is quite complicated and was laboriously protracted in the name of handling balance by the Honda chassis engineers. Of course, it is expected that lowering a vehicle will thereby alter this trigonometrically dictated ballet and will generally upset some of the compromises built-in from the factory. The "alignment" of common suspension angles that compose the geometry are greatly effected by lowering and this writing is intended to bring those changes to light.
The three angles to consider in the alignment settings are caster, camber and toe. All of these suspension settings dictate important considerations in terms of handling, feel and tire wear. Caster is somewhat built-in to the chassis and is non-adjustable on a typical Honda. Generally we are not concerned with adjusting it outside of race-level performance enhancement. It doesn't move much when a car is lowered.
Cusco camber plates provide easy camber adjustment on strut suspension cars like DC5s and EP3s.
Camber is the most dramatically effected setting when lowering a car. This is the characteristic "tilt" of the wheel on a slammed car. The top of the tire leans into the wheel arch, and in drastic cases (especially on EF and DA chassis), the angle is so severe you'd swear the wheel is about to fall off. Nearly all automotive suspensions are designed to exhibit a certain amount of camber, which is measured in degrees. An age-old gripe within the Honda Tuning community is that there is no ability to adjust this angle with the factory suspension arms.
In fact, the only suspension angle to which Honda does provide adjustment is to the toe angle. This is the baseline steering angle, easily remembered if you liken it to looking down at your feet: Toes pointed in or out will simulate the toe conditions on a car. Toe is probably the most important angle we consider since it is adjustable and it's setting impacts the car the most. If the steering wheel is off center, or the car pulls to one side or the other, toe is the typical culprit.
These toe links from Cusco offer additional rear toe adjustment on the RA chassis Odyssey. They provide the additional range that is needed when lowering.
When a car is lowered, the tires will toe-in or -out fairly dramatically, depending on the design of the suspension. The odd thing that happens is, the toe is impacted evenly on both sides, so when the toe is even there is no pull. Many people mistakenly think that because there is no pull no alignment adjustment is needed. Unfortunately they find out instead that their tires have worn out very quickly and need to be replaced.
It is important to realize that all cars have positive caster built-in (adjustable on some cars, but non-adjustable on a Honda). This means that when you turn the wheel, the axis of rotation is not vertical. You may notice caster to be more exaggerated on European cars. The best way to view the caster angle is to turn the wheel all the way to one side and get out and look at your car. Notice that the wheel is turned but also somewhat flopped over? Have a friend with a Mercedes S500 do donuts while you watch outside. The wheels really flop over on those tanks!
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