This RC8 is set “bones level,” meaning the
driveshafts are parallel to the ground.
Some cars use threaded collars to adjust ride
height; others use clip-on spacers, as seen here.
Literally the height at which your car rides, this
adjustment is a biggie but also an easy one to
get right. Most off-road cars are designed to run
either “arms level” or “bones level.” Place your
car on a table, settle it on its suspension, and
then eyeball it directly from the front or rear.
Note the angle of the arms; if they form a
straight line, that’s “arms level.” You may note
the dogbones (driveshafts) slope from the chassis down to the wheels when the suspension is
set “arms level.” Likewise, if you set the suspension “bones level” so the driveshafts form a
straight line, the arms probably slope upward
from the chassis to meet the wheels. Now view
your car from the side; the chassis should be
level with the table’s surface. Changing ride
height changes the car’s center of gravity. On
high-grip tracks, running the car lower can reduce body roll, helping the car transition from corner to corner faster. In low-traction conditions, raising the ride height
may help increase grip by allowing more weight to transfer to the outside wheels
when cornering. You can also raise or lower one end of the car independent of the
other—the lower end will generally gain traction. Setting ride height is easy, whether
your shocks are threaded (just turn the spring collar to adjust ride height) or use
clip-on spacers (add spacers to increase ride height, remove them to lower it).
Viewed from the side, this RC8 has a very slight “rake”; the front ride height
is just slightly lower than the rear. By lowering or raising either end of the car,
its handling balance can be altered.
Take a “direct overhead” view of your car, and you’ll see
that the rear wheels point in slightly towards the chassis,
while the front wheels may point slightly in, straight
ahead, or slightly out. This angle is known as “toe,” and
as you might guess, it’s “toe in” if the tires point in, and
“toe out” if the tires point out. Most cars have fixed rear
toe-in, or it may be adjustable by swapping a few parts.
Front toe, however, is easily adjusted via the tie rods.
4WD cars typically have zero front toe (the wheels point
dead ahead), but 2WD cars usually have a slight
amount of toe-in. This helps with stability because the
front tires are steering toward each other, however
slightly, even as the car is going straight. A little toe-in
also counteracts the tendency for any play or flex in the
suspension and steering system to cause the wheels to
toe out. If you want your car to initiate turns more
aggressively, reduce toe-in or try slight toe-out. A little
goes a long way, so make small adjustments.
4WD buggies typically have zero front toe or slight toe-out,
and 2 or 3 degrees of rear toe-in.
THE END (OR THE BEGINNING)
Is it really that simple? Well, no; we could get into setting
droop, the difference between setting spring preload and
ride height, the relationship between caster angle and
steering-induced camber gain and much more. But for
the practical purposes of making meaningful changes to
your suspension setup, the concepts discussed here will
go a long way in helping you understand what makes
your car handle—or not. Experiment, keep notes, and
don’t be afraid to try stuff that’s “not supposed to work.”
You can always go back to the stock settings!