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.
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.
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!
Think of it like pushing a wheelbarrow. The angle from the axle to the handle is like caster. Pick up a wheelbarrow and stand it vertically on the tire with the handles straight in the air. Imagine pushing it and trying to turn it. Now, imagine pushing and turning it normally and notice how much easier and stable it would be. When you turn a wheelbarrow notice there is no steering, the front wheel leans! That is how motorcycles turn as well, and to a less exaggerated extent that is how your car turns too.
Caster is great for high-speed stability. That is why all cars have some dialed in. Without it, the car would be twitchy and hard to control. That explains why autobahn burners have more caster than your typical Japanese car. It doesn't greatly impact tire wear on its own, but it can induce a pull in the suspension if it is drastically different from side to side. Excessive caster will cause slow and lethargic steering and combined with toe-in, it is downright deadly for tires.
Camber gets somewhat of a bad rap within the automotive industry. The typical premature wear pattern people notice on a lowered car is due to excessive inner tire wear. People naturally associate the leaning of the wheel with this inner wear. Thus, they determine the fix for the wear is to install a camber kit which will allow adjustment of the camber. If tire wear is your concern, know that camber alone is not to blame. The reality is that a bad toe setting will wear tires much faster than camber will.
Actually, camber can be a very good thing. To some extent, some negative camber will actually benefit the car. When a double-wishbone suspended car such as the '88-'00 Civics, '90-'01 Integras, Accords or TSXs, the camber angle always increases in a negative direction whenever the suspension moves up. It's what makes the car handle better in turns than the strut cars, which have negative camber but not nearly as much, generally speaking. It is a natural affect of cycling a double-wishbone suspension.
As the car is turning hard, the outside suspension becomes loaded and the tire tends to roll under the wheel rim. With a zero camber setting, the tire would be aggressively pulled under and the car would actually be riding on the outside of the tire with a reduced contact patch. As a double-wishbone suspension is loaded, the camber angle becomes more negative tilting into the turn and effectively pulling the tire back under the wheel through the turn. The end result: With negative camber the contact patch will be larger through turns.
Imagine that when such a car is lowered, the suspension's neutral stance will actually be the result of moving the wheels up as though they were "preloaded." The suspension "thinks" it is constantly cornering, even when it is going in a straight line. Camber is negative and toe is in. On-center feel generally deteriorates, as do the tires on the inside edges.
At this point, you may be wondering what is doing the damage to the tires the toe or the camber? To answer the question we must forget conventional wisdom and simply look at some tires.
Look where the inside and outside of the tire are. The red circles [above] are there to help you identify the wear-indicators inside the tire grooves. When the tires wear down to these wear-bars, you know it is time to replace the tires. These tires are almost there. You can see how the tire is worn more toward the inside. This is camber wear. This car was lowered moderately with a good alignment. The person who drove on this tire has not maximized tire wear, but clearly hasn't suffered greatly either. No camber kit was installed to fix the camber.
Here [right] we have a tire that was lowered aggressively and the car was not aligned and has a raw toe setting. Look how aggressively the tire has worn on the inside edge, so much so that the cords are even showing. This wear is caused by toe angle. The direction of wear here is dramatically different than a camber-worn tire. This type of wear will kill a brand new set of tires in a matter of months.
So why does the wear happen? Simply put, the toe-in condition coupled with positive caster and negative camber, will concentrate all of the tire wear on the very inside edge of the tires. In a straight line the tires should just roll with minimal wear. The perfect storm of misalignments induces a wear when going straight, and so the inside edges wear out very fast. Simply adjusting the toe will resolve 90 percent or so of the issue.
Oftentimes, people will lower their cars and fail to align them when they don't feel any pull. This dramatic wear pattern results and the users tend to blame it on camber. The timeline continues when the customer buys a camber kit, installs it, aligns the car and the wear goes away. Must have been the camber causing the wear, right? It was the toe being adjusted during the alignment that stopped the wear. The camber kit only marginally helped improve tire life.
In fact, the added camber actually makes the car handle better when driven harder. In a car that is driven aggressively (onramp bombers, we're talking to you) one would actually notice outer tire wear and reduced traction if camber were at the zero setting. With negative camber in place, aggressive drivers will notice an even wear pattern, rather than inner or outer wear.
Our general recommendation is that the car should be lowered to your desired height then given a proper alignment to adjust the toe. The conscientious user should then monitor the tires and rotate them frequently to raise awareness of tire conditions. If drastic wear patterns develop it can be caught and fixed long before they need to be replaced.
If camber kits are not necessary why are there so many available? The fact is camber kits need to be available to those who actually need them. The finer a car is tuned, the more control a driver will want to have over alignment settings. Adjustability is the key to getting dialed in. Individuals using very expensive oversized wheel/tire combinations generally strive to get every last mile out of them before replacement is needed. Fixing the camber is the only way to ensure a completely even wear on a car built for cruising.
When a car is lowered and the camber goes negative, the contact patch is compromised when it goes straight. Obviously this is bad for you drag racers and you'd want to maximize your contact patch by fixing the camber.
Negative camber is visually apparent from outside of the car. This is a big deal to some people and it is a look that is not always desired. This is particularly true of the Accord, TSX and TL crowd where the aim of lowering is to reduce tire gap, and unwanted camber angle is unsightly. The need for a camber fixing solution is clear.
Caution should be taken to opt for the best quality camber kits as well. Some units will replace factory Honda bushings or ball joints with aftermarket adjustable units. There has not been a comparable consistency in life or quality from aftermarket items with factory pieces here. Expect that installing a camber kit on your car may not be a permanent solution and that the replacement of a part may be due sooner than you expect.
There are many reasons to modify your car. Performance, appearance, personal satisfaction and pride of ownership all come to mind. With all the factors that need to be considered when designing a car, shouldn't at least some of this knowledge be present when modifying it? Our goal is to ensure that educated choices are made when choosing the products to put on their cars.