Wiping the sweat from your forehead, you hop into your ride after finishing a complete suspension rebuild. Ball joints, springs, shocks, tie rods, all the good stuff that keeps your wheels pointed straight are all new. It’s time to cruise down to the local watering hole and enjoy the fruits of your labor. As you back out of the driveway, things seem good, but then as you approach 40 MPH, you notice that the car is pulling to the left and tires are scrubbing. You need to turn around to go back home because your ride needs an alignment.
Any time that any mods are performed on the suspension, you need an alignment. The slightest adjustment to the caster, camber, or toe can wreak havoc on your vehicle’s handling, and will also destroy your tires at the same time. While most of us take our cars to the alignment shop to get this done, you can do it at home with the QuickTrick Alignment system. Before we get into the kit, let’s talk a little about what an alignment does.
There are three main settings in alignments: camber, caster, and toe. Each has its own handling characteristics. Every vehicle requires different settings for each and your driving style affects the setting as well if you are aligning for performance driving.
Simply put, this is the angle of the vertical side of the tire. Negative camber tips the top of the tire inward towards the engine, where positive camber tips the top outward. This spec is noted in degrees, positive or negative. Most vehicles use negative camber settings. This tips the tire in slightly at the top. The more aggressive the driving, the more negative camber you want—to a point. Too much negative camber wears out the inside of the tires faster and can yield camber thrust, where bumps in the road can cause the vehicle to move across the road as one tire loses grip, the opposite pushes toward the loss in traction. Another drawback of aggressive negative camber is reduced straight line traction for stopping and acceleration. Positive camber is sometimes used in front-wheel drive vehicles, which are usually non-adjustable in terms of camber.
Caster, measured in degrees, is a little harder to explain, mainly because you can’t really see it on the car itself, which is why we are using a bike for visualization. The pivot point on a bike is behind the roll center of the wheel, if you drew a line through the center of the pivot point, it would run from the top rear to the front bottom, this is negative caster. Negative caster keeps the wheels pointing straight and stabilizes the vehicle. If the caster was neutral, the wheels would not be stable, the car would wander on the road, especially above 50-60 MPH, and the steering wheel would not return to center after a turn.
Caster allows the suspension tuner to balance stability, cornering, and turning effort. Positive caster yields better straight line tracking and high-speed stability, but at the cost of very high turning effort. Even with power steering, positive caster makes turning the steering wheel more difficult. For this reason, most older vehicles use negative caster.
Caster adjustment is typically made at the upper control arm or upper strut mount, fore and aft.
The toe is the direction of the tires, running front to back. Toe-in points the tires together in the front, toe-out points the front of the tires away from each other. Toe does several things- It stabilizes the vehicle in straight line driving, and compensates for the vehicle’s tendency for over or understeer. Measured in either degrees or inches, toe is critical for tire wear. Too much toe scrubs the tires, wearing them out quickly and kills straight line speed. Not enough toe can make the car wander around the road. Toe adjustments are very small, often just 1/32 of an inch per side.
Toe-in is most common on rear-wheel drive vehicles, where the rear wheels push the car. The toe-in helps counter the natural oversteer in RWD vehicles. Because the rear tires push the front of the car, the front suspension bushings tend to walk outward at the front. The toe-in manages this tendency, keeping the car on track.
Front-wheel drive vehicles typically use toe-out. Because FWD cars often have understeer, where the front end wants to go straight instead of turn, toe-out reduces understeer during the initial turn-in. Because FWD cars are being pulled by the front wheels, the front bushings are typically pulled forward, the toe-out is the compensation.
Toe is adjusted through the tie-rods.
Setting the alignment is a matter of trial and error adjustments. With a professional laser-guided computerized alignment machine, it can be done in a couple of hours. These machines cost thousands of dollars and the average gearhead does not have the room for such a piece of equipment, nor the need to use it often enough to justify the cost. There is an alternative, however, and it is called the QuickTrick Alignment system. For less than $300, you can get started setting your own alignments. The basic system uses a pair of wheel clamps that hook onto your wheels, up to 22.5” rims and 38” tires. The clamps connect side to side with measuring tapes that lock into the bars. A magnetic level is used on the vertical bar to check caster and camber.
The process for measuring each setting involves a little math and some set up. All of these processes can be done by one person, but having a helper certainly makes it go faster. We set out to determine the handling issues on our 1963 Buick Le Sabre wagon after rebuilding the front suspension. Using the QuickTrick alignment tools, we were able to get the car set up correctly and now it drives smooth down the road.