User Manual

Differential Fluids
Changing the viscosity of the fluid in the
differentials affects the way the car handles and
performs. The Mayhem differentials come pre-
filled with 5000 wt. fluid in the center and front
and 1000 wt. fluid in the rear. For most
conditions, this is a good place to start.
Center: Changing the fluid in the center
differential affects the front to rear drive. To
conceptually understand how the center
differential affects handling, think of it as front-
wheel vs. rear-wheel drive. Heavier fluid gives
more rear-wheel drive effect, resulting in
more acceleration and more on-power steering.
Lighter fluids in the center differential allow the
front tires to unload during acceleration, giving
more front-wheel drive and reducing power-on
steering. When your car under-steers during
acceleration, try switching to a heavier fluid in the
center differential. When your car over-steers
during acceleration, try switching to lighter weight
diff fluid in the center. Typically the optimum
center differential fluid is between 3,000 to
10,000 wt. depending on track conditions (slick
surfaces = lighter center diff fluid).
Front: The viscosity of the fluid in the front
differential affects overall steering authority.
Heavier fluid reduces steering while lighter fluid
gives more steering. However, if the
fluid used in the front diff is too light the steering
can become inconsistent, especially when
accelerating from corners. Typically
the optimum front diff fluid is between
3000 and 7000 wt.
Rear:The fluid in the rear differential affects
cornering traction and overall steering.
Lighter fluid in the rear diff gives more cornering
traction and more steering, while heavier fluid
reduces rear side bite while reducing steering
authority. Some racers replace the fluid in the
rear differential with thin grease for even greater
rear cornering traction. Nearly all racers use
1000 wt. fluid or light grease in the rear
differential to get maximum rear end traction.
Choosing Tires
The single most dramatic factor affecting
your car’s handling is tires. Before you begin
changing your setup, it’s important to
choose the best tires for the conditions.
While experimenting with various tread designs,
compounds and liners is the optimum way to find
the best combination, it’s time consuming. If time
is limited, find out what tires the fast guys are
using and duplicate their selection.
Caster
The Mayhem offers two caster positions: arms
forward and arms rearward. Moving the clip in
front of or behind the upper front arms easily
changes caster position. The rearward position
gives slightly more steering in the midsection and
exiting turns, while reducing the steering on
entry. The arms forward position gives more
steering at corner entry, while slightly reducing
the midsection and exit cornering authority.
Shock Locations
The Mayhem offers three lower rear shock
positions and two lower front positions. Several
upper shock locations are available.
Lower Shock Positions:Moving the lower shock
mounting position will change the suspension’s
mechanical advantage. Moving the mounting
position inward has a similar effect as using
softer springs and lower weight oil. Moving the
lower mounting position outward is similar to
stiffening the spring rate and increasing the oil
weight.
If the suspension is too soft (bottoming out),
moving the lower shock outward will increase the
rate. If the suspension is too hard (lack of
traction), moving the lower suspension mounting
position inward will decrease the rate giving more
traction. Remember the optimum setting is a fine
balance between the front and rear.
Upper Shock Positions:Moving the upper
shock mounting position inward gives a more
progressive spring and damping rate.
Progressive rate means as the shock is
compressed, the spring and dampening rates
increase more quickly. Standing up the shocks “to
their outer mounting positions” gives more linear
dampening and spring rate.
Note: There are two sets of upper mounting
positions located on the shock tower. The
uppermost holes are used when the shock is
positioned in the inner mounting position on
the arms. The lower set of holes is used
when the shocks are mounted in the outer
suspension’s arm positions.
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