Static Suspension
Strongs Of Center (Part 3).
Top
mounts.
These
are the items that locate the top of the suspension strut in the correct
position on the car’s chassis. From the factory they tend to basically be a
large rubber bush that absorbs the stress and vibration that would otherwise be
transmitted to the chassis from the suspension. Uprated items tend to be made
of either polyurethane, or solid metal with a rose joint to mount to the shock
absorber, to improve handling response and control. Some aftermarket top
mounts, as well as being solid with a spherical bearing, allow the shock and
spring position to be relocated a few cm within the suspension towers, giving
you a decent amount of camber and sometimes even castor adjustment.
These are the items that locate the
top of the suspension strut in the correct position on the car’s chassis.
Anti-roll
bars.
ARBs
are another form of torsion bar, but these are fitted to the front and rear of
almost all cars these days. Their job is to supplement the conventional
suspension springs rather than replace them. As you might have guessed, ARBs
exist to help resist body roll – if you simply made the shocks and springs
stiff enough to eliminate body roll on their own the suspension would be too
hard to work properly on the vast majority of surfaces. Thicker and stiffer
ARBs are a common aftermarket upgrade, and some high-end versions are actually
adjustable; in fact, some race cars have in-car adjustable ARBs, enabling the
driver to adjust roll stiffness while out on track! ARB settings are a good way
to change the handling characteristics of the car too, with a stiffer rear bar
tending to increase oversteer, and a stiffer front bar tending to increase
understeer.
ARBs are another form of torsion bar,
but these are fitted to the front and rear of almost all cars these days.
Rose
joints.
These,
in car suspension use, tend to be used to replace suspension bushes on the ends
of suspension arms in fast-road and especially race use. These are solid metal
spherical bearings that will allow the arms to move in their specified arcs just
as intended from the factory, but while totally eliminating the flex the rubber
bush gives. The main advantage of getting rid of the flex is improved precision
of suspension and steering feel, but the side effect is a stiffer ride and a
much shorter life span than production rubber joints.
These are solid metal spherical
bearings that will allow the arms to move in their specified arcs just as
intended from the factory, but while totally eliminating the flex the rubber
bush gives
Subframes.
Not
all cars have these, as some have the suspension arms mounted directly to the
chassis, but subframes are the solid frames that the suspension arms are
connected to on the front or rear of many cars. Subframes are specially
designed so the suspension arms are connected at the perceived perfect position
for the standard production vehicle, but on a modified version of the car these
positions are often far from perfect. Unfortunately modifying a subframe is no
easy task and it’s rarely done outside of hardcore race cars, but on some
vehicles, custom tubular subframes that not only save weight, but mount the
arms in optimal position for race use do exist; if you can afford them that is!
The solid frames that the suspension
arms are connected to on the front or rear of many cars
