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Slayer
This advanced tuning guide will take you one step further into the
cutting edge technology that has been designed into Slayer. Follow
the instructions provided here to take advantage of Slayer’s maximum
performance potential.
SUSPEnSIon AnD AlIGnMEnT SETTInGS
Caster Adjustment
The caster angle of the front
suspension may be used to adjust
the understeer (push)/oversteer
handling characteristics of the
model. Generally, increasing the
caster angle will move the truck
towards an oversteer condition
(more traction on the front tires, less
on the rear tires). Decreasing the
caster angle will create a tendency
towards understeer (pushing in the
turns). From the factory, the front
suspension is set to a caster angle of
10-degrees. The rear caster angle is
not adjustable. The caster angle
of the front suspension can be
adjusted from 5° to 15°. Adjust
the caster by positioning the
caster adjustment shims on the
upper control arms of the front
suspension as shown in the
table to the right.
Caster Angle, and Bump Steer
Bump steer is unwanted change in the steering angle of the front wheels
as the suspension travels up and down. It can result in unstable and
unpredictable handling. Bump steer is affected by the position of the
outer toe link end on the axle carrier. From the factory, the toe links are
positioned so that bump steer is virtually eliminated (about 3/100 of
a degree through the entire range of travel). When the caster angle is
changed, the outer toe link end should be repositioned on the axle carrier
to maintain zero bump steer geometry. Adjustment is achieved using the
shims and hollow balls provided with the vehicle. Refer to the Bump Steer
Elimination chart on page 41, and look up your caster angle setting to
find the correct position for the outer toe links. Positioning the toe-links
correctly will maintain the original factory geometry and eliminate the
unwanted steering angle changes caused by bump steer.
Roll Center
There are two holes on the
bulkheads to mount each upper
suspension arm. The roll center
of the vehicle can be raised by
mounting the upper control arm in
the lower of the two holes. This will
effectively increase the roll stiffness
of the vehicle (similar to installing
swaybars). Adding roll resistance to
one end of the vehicle will tend to
add traction to the opposite end. For example, increasing roll resistance in
the rear by installing the upper arms in the lower holes will provide more
traction for the front wheels and potentially more steering. Installing the
upper arms in the lower holes on the front and rear will increase overall
roll resistance without changing the handling balance. The arms are
installed in the upper position from the factory to make the truck easier
and more forgiving to drive and less likely to traction roll in turns. The
lower holes should be reserved for track tuning.
Note:
When the upper
suspension arms are moved to the lower holes, the front outer toe link
ends and the rear toe control links should be repositioned to eliminate
bump steer. Refer to the Bump Steer Elimination chart on page 41,
and look up your suspension combination (caster angle and roll center
position) to find the correct position for the front outer toe links and the
rear toe control links. Adjustment is achieved using the shims and hollow
balls provided with the vehicle.
Rockers (Progressive Rate/ Suspension Travel)
One of the most exciting aspects of Slayer’s suspension is the inboard
shock (damper) arrangement that uses pivoting rockers to translate
vertical wheel travel into linear shock motion. The rockers can be changed
to increase the progressive rate of the suspension.
The progressive rate determines how much the force at the wheel
produced by the springs being compressed (wheel force) will vary with
suspension travel (or vertical travel of the wheel). On a progressive
suspension arrangement, the wheel force will increase at a faster and
faster rate as the suspension is compressed. It feels as though the shock
spring gets progressively stiffer the more you compress the suspension.
On a linear suspension arrangement, the wheel force increases linearly as
the suspension is compressed. The spring does not feel any stiffer, even
when the suspension is fully compressed. This provides a very “plush”
feeling suspension with seemingly bottomless suspension travel.
Caster adjustment shims (2 front, 2 rear)
Vertical
Ground plane
10°
Upper Control Arm
Upper Mounting Holes
Upper Control Arm
Lower Mounting Holes
Caster
In Front of
Hinge Pin Boss
Behind Hinge
Pin Boss
5.0°
None
Four
7.5°
One
Three
10.0°
Two
Two
12.5°
Three
One
15.0°
Four
None
Number & Position of Caster Adjustment
Shims (Front Upper Control Arm)
Advanced Tuning Adjustments
