K021 Instructions v1.0
Tuning
Page
75
ease of adjustment: have a friend take a ¼” wrench out to the track, and a few brief pit
stops later you can have the car completely dialed.
Adjusting the differential for track performance is a tougher science, especially since the
adjustment window is pretty small – less than full turn on the diff screw can go from too
loose to locked up. The idea is, the looser your diff is, the more corner speed the car
will carry. A tighter diff will have more forward bite – kind of like running a locked diff in
a drag car. Diff adjustment isn’t changed often but can be useful; always be sure the
slipper gives before the differential barks.
FRONT CASTER
Your X – 6 Squared comes with 30
o
caster blocks. These give the car great corner
entry steering while keeping it stable on exit. There are also 25
o
and 20
o
blocks
available (ASC #9580 and #9592, respectively), which will progressively take away from
turn in while adding exit steering. Honestly, the XF team worldwide runs the 30
o
blocks
almost exclusively; there are usually better ways to gain steering without losing stability.
STEERING BLOCKS
One way to increase steering is to switch from the stock trailing axles to inline axles
(ASC #9623) and inline steering blocks (ASC #9577). When you install these parts,
move the spacer from behind the caster blocks (installed in step A9) to the front, and
use the rear Ackerman hole in the steering rack. These axles will give much more
aggressive steering in and out of the corner, though they sacrifice straight-line stability:
they can make the steering feel twitchy. To combat this twitchy feel, many X Factory
drivers have experimented with running the inline axles while leaving the caster blocks
forward. This extends the car’s wheelbase while taking some weight off the front tires,
all of which smoothes out the car’s steering.
ANTI-SQUAT
Rear anti-squat is the angle of the rear hinge pins relative to the ground. Lowering the
rear toe-in block by removing spacers increases the amount of anti-squat in the car.
With no spacers, the car has 4
o
of anti-squat; with approximately .120” (3 mm) of
spacing the car has 0
o
, so every .030” (.74 mm) of spacers is a degree less. The thin
white nylon shims included in the kit are .030”; the thicker ones are .060”.