The steering and suspension system in your car may look simple enough, but in actuality it's a complex series of arms, links, springs, and pivots. All of it is there to do a few basic things, like soak up bumps in the road, track straight and allow you to turn corners. The car is stuck to the road by four relatively small contact patches, so the alignment settings also manage that contact patch and keep it as large as possible while the suspension cycles. Even though the stuff is there to do these basic things, there are settings you can adjust even on a brand new vehicle to make it handle better and make the tires last longer.
What does all of this have to do with the musclecar owner? Well, if you have upgraded to radial tires, wider tires, lowered the car, or are prepping the car for an autocross/open track day, you will need to have the alignment set for those new parameters. Let's face it: There's nothing worse than having your car wander all over the road and eat front tires for breakfast. Plus, the proper wheel alignment, whatever the application (street, strip, autocross/road course or a top speed assault) will maximize your suspension's potential and deliver the best possible performance.
Once Corey had Drew's Camaro...
Once Corey had Drew's Camaro up on the alignment rack, he adjusted the toe, camber, and then came back and reset the toe. Changing the camber will always change the toe settings a bit.
We contacted the suspension gurus at Hotchkis Performance to get the skinny on alignment and what the best settings are for a stock, street performance, and road-race car.
While we were there, Aaron Ogawa, the chief engineer at Hotchkis, also showed us how to read tire temps to diagnose alignment and tire pressure issues.
We used a '69 Camaro owned by Drew Oliver, who works at Hotchkis and beats the F-body up on autocross courses on a regular basis. The car was pulling to the left instead of tracking straight, one sure sign the alignment was askew. It's not a bad idea to check the front end alignment often if you do frequent open track or autocross events, as these harsh environments can cause the setting to change.
Toe-in is when the front of...
Toe-in is when the front of the tires are closer together than the back of the tires. Setting a car with toe-in will provide greater straight-line stability, but you will see a little more tire wear and a little less steering response. Even though toe-in will place a little more wear on the tires, it is still recommended for street driven cars.
While the car was up on the rack, Corey Bedortha walked through a few checks to determine why the car was pulling to the left. Come to find out the left side of the car had less negative camber, but after getting it back to spec the car was ready for the next event.
Most Factory Settings
(bias ply tires)
0.5 Negative Camber
0.5 To 1.0 Positive Caster
0.24 Toe-In
Good Street Performance Settings
(radial tires)
0.5 Negative Camber
3.5 TO 4.5 Positive Caster
0.10 Toe-In
Good Autocross Settings
(will need aftermarket components to achieve these settings)
2.5 TO 3.0 Negative Camber
4.0 TO 6.0 Positive Caster
0.0 Toe-In (Big Course)
0.10 Toe-In (Short Course)
Toe-out is when the front...
Toe-out is when the front of the tires are further apart than the back of the tires. Setting a car with zero toe or toe-out will make the car wander, but will improve turning radius and steering response.
A Few Definitions
Caster
Caster angle is basically the angle of an imaginary line that runs through the center of the upper ball joint to the center of the lower ball joint. The car will always be set with positive caster as it improves high speed stability, helps the car track straight, and improves the tires' contact patch during a turn by complimenting the camber setting. Too much positive caster will slow steering response and make the car hard to turn.
Oversteer
Oversteer is when the back end of the car breaks loose and slides toward the outside of a turn.
Understeer
Understeer is when the front end of the car breaks loose and slides or pushes toward the outside of a turn.
 Negative camber means the...  Negative camber means the bottom of the tire is out further than the top. Having some negative camber in your suspension will make the car more controllable because you won't be rolling the tire over and losing the inside contact patch when cornering hard. Also, negative camber will make the car more likely to oversteer. We would prefer the rear of the car to pitch sideways because once you get the hang of it you can control the drift, which is the fast way around the track makes for cool pictures. |  Positive camber means that...  Positive camber means that the top of the sticking wheel is out further than the bottom in relationship to the car. Typically there is no reason to have any positive camber unless you are a circle track racer. Then you might benefit from having a little positive camber on your inside tire only. |  Thrust angle is the measurement...  Thrust angle is the measurement to tell you if the rear end of the car is squared under the frame. If you have ever seen a car that is going down the road a bit crooked, it could be an out of whack thrust angle. If the thrust angle isn't right on a leaf spring car, you can loosen the U-bolts a bit and try to get the rear end squared up, but that won't do much. If the angle is way out you will need to have the frame checked; it's probably bent. |
 If you have just lowered your...  If you have just lowered your car you should adjust the toe setting before driving the car to the alignment shop. The best way is to use a stick like this one. If you don't have one of those grab a friend and a tape measure. Pick a spot in the middle of the tread and measure the distance in the front and the rear. You want the front measurement to be 1/16 of an inch smaller than the rear. If it's not, then adjust the tie rods until you get that spec. Now you can drive to the alignment shop without smoking your tires. Well the front ones at least. |  "Checking tire temp is critical...  "Checking tire temp is critical after changing your alignment or tires. Using a temp gun or pyrometer, measure the temperature in the inner, middle, and outer zones of the tire. If you have excessively hot temps on the inside of the tire, then you may have too much negative camber. If you have excessively hot temps on the outside area of the tire, then you need more negative camber. High temps on the inside and outside areas simultaneously, typically indicate low tire pressure. A high temp in the center of the tire usually means the pressure is too high. A good baseline alignment and tire pressure will yield even temps throughout the width of the tire."-Aaron Ogawa |  "Tire pressure can make a...  "Tire pressure can make a huge impact on handling balance. When you take your car to the track or autocross, set your tire pressures based on the criteria at the bottom of the previous page. After the first few laps, determine whether or not the car is showing too much understeer or oversteer for that particular course. If you want more oversteer, you can increase the rear tire pressure to decrease the traction in the rear and/or decrease front tire pressure to increase traction in the front. Vice versa for less oversteer. Be careful to make few adjustments at a time, so you can track your changes accurately. Every course is different, which may require different pressure settings. Remember tire pressure increases with heat, so pressure maintenance is vital."-Aaron Ogawa |