SLAYER PRO 4X4 • 29
BASIC TUNING ADJUSTMENTS
This tuning and setup guide is separated into two sections- Basic and
Advanced. Slayer Pro 4x4 does not require any specialized knowledge
or understanding of its unique suspension and drive train to perform
typical, everyday setup and track tuning adjustments. Adjustment
procedures for alignment, spring rate, damping, steering, and ride
height are covered in the basic tuning section. Adjustments for the
gear ratio, two-speed shift point, slipper clutch, and brake are also
covered. In most cases, the basic information is all that is needed to
tune Slayer Pro 4x4 to perform well on a variety of surfaces.
Slayer Pro 4x4 was engineered to provide sophisticated additional
tuning options well beyond the basics that allow expert users to
extract the maximum performance from the truck. The advanced
tuning section (beginning on page 36) covers topics such as optional
suspension rockers, roll center adjustment, caster adjustment, bump
steer tuning, differential setup, and fine tuning the two-speed
gear ratios. Make sure you fully understand the basic adjustments
before experimenting with the advanced adjustments. Improper
combinations of adjustments can adversely affect the performance of
the truck, resulting in poor handling. If you don’t know why you are
changing an adjustment then you should leave it at its factory setting.
SUSPENSION TUNING
Springs
The front and rear
springs on Slayer Pro
4x4 have different
spring rates. The rear
springs are about 12%
stiffer than the front
springs. The spring’s
pre-load tension can
be adjusted by turning
the spring pre-load
adjuster. Adjusting the
pre-load changes the
suspension sag and ride
height. Suspension sag
basically defines how much the suspension compresses when the
truck is at rest. Adjust the pre-load so that the suspension compresses
about 1/3 of its full suspension travel (see illustration). If suspension
sag is severe and requires a large increase of the spring pre-load to
compensate, then a firmer spring should be used.
Use a stiffer spring to reduce sag, reduce body lean, control brake
dive, and provide a firmer, more responsive overall feel. If Slayer Pro
4x4 is lightened significantly for racing applications, softer springs
will be necessary to allow the suspension to sag properly. Heavier
configurations will require stiffer springs. The suspension sag
and spring pre-load should be readjusted anytime the springs are
removed and/or replaced.
Optional springs available from Traxxas are listed below. Refer to your
parts list for a complete part number listing. Higher rate springs are
stiffer. Springs can be identified by dots of color on one end.
Ride Height Adjustment
The rocker arm suspension uses push rods on each suspension arm.
Changing the length and/or position of the push rod adjusts the
ride height without affecting or compromising other suspension
parameters. For example, you can raise the ride height of the rear
suspension without changing up/down travel distribution, changing
springs, or affecting your progressive rate. Increasing the rear ride
height will increase ground clearance for rough terrain. The rear ride
height of the model can be changed by mounting the push rod in
the inner hole in the lower rear suspension arm. From the factory,
the rear push rod comes installed in the outer hole of the lower rear
suspension arm’s push rod mount. If the push rod is mounted in the
inner hole, the ride height of the vehicle increases. The ride height
can be tuned by adjusting the sag of the suspension. If suspension
sag is severe and requires a large increase of the spring pre-load to
compensate, then a firmer spring should be used.
Compression 2/3
Sag (Droop) 1/3
Ride Height
Total Travel
Axle Centerline at Ride Height
Axle Centerline at Max Compression
Axle Centerline at Max Sag
Important:
The shocks are
assembled at the factory
with a center-to-center
distance (between the rod
end balls) of 82mm. Any time
the shocks are removed and
disassembled, this distance
should be checked to ensure
proper operation of the
suspension.
82mm
Spring Color Stripe Color
Spring Rate
Red
Double Pink
1.4 N/mm (8.0 lb/in)
Red
Double Blue
1.6 N/mm (9.1 lb/in)
Red
Double Green
1.8 N/mm (10.3 lb/in)
Red
Double Black
2.0 N/mm (11.4 lb/in)
Red
Double Purple
2.3 N/mm (13.1 lb/in)
Red
Yellow
2.6 N/mm (14.8 lb/in) (Standard Rear)
Red
White
2.9 N/mm (16.6 lb/in) (Standard Front)
Red
Orange
3.2 N/mm (18.3 lb/in)
Red
Green
3.5 N/mm (20 lb/in)
Red
Gold
3.8 N/mm (21.7 lb/in)
Red
Tan
4.1 N/mm (23.4 lb/in)
Red
Black
4.4 N/mm (25.1 lb/in)
