SETUP STUFF
by Charlie Perez on RC10B4.com Forum
Compilation by Elvo on RC10B4.com Forum
This is BASIC RC10B4 setup info BUT the understanding of WHY this does
that, works on any off-road car/truck.
***
Moving the Steering Spindle Up and Down changes two things.
(1) It changes the Total down travel your front end has. More Down
travel in the front will give you more predictable landing off of
jumps. It will also give you less steering as you exit the corner on
power. Less Down Travel in the front will make your car less
predictable landing off of jumps, such as sticking into the dirt like a
lawn dart if you land extremely nose down. The advantage of less down
travel is increased corner exiting steering when you are on power. I
like to use this adjustment to quickly see if increasing or decreasing
the downtravel in my shocks will provide the corner handling that I
desire.
(2) The spindle height will also change the amount of bump steer your
car has. Lowering the spindle will give the front end more Bump-In.
Raising the spindle will give the front end more Bump-Out. This is if
you do not add or take out any washers under the steering ball end.
Bump-In will give you more steering entering and through the corner. It
will also make your car feel more aggressive to initial steering
inputs. Bump-Out will give you less steering entering the corner but
more through and exiting the corner. So in high speed sweepers Bump-Out
will give you a more consistent steering “Feel”.
Bump-Out will also
dull some of the initial steering inputs. I personally like to use Zero
bump in or out. So if I change the height of the spindle I have to add
or subtract shims from under the ball end to keep the Bump at Zero.
***
If your car wants to nose dive off of jumps then stick on the landing
like a lawn dart give the following suggestions a try.
(1)
Raise the rear ride height to just above dog bones level. This will
keep the car from "Bucking" the rear end up over jumps. The
disadvantage to this is that the car will have less side bite as you
enter the corners.
(2) Increase the front down travel of
the shocks. Stock down travel limiting is .090 of shims. Take out one
of the shims so your down travel limiting is .060. With the increased
front down travel this will make your car more forgiving on the
landings that are nose down. The disadvantage of increasing the front
down travel is a loss in corner exiting steering.
***
What is the difference between 1-B with 3 washers and 1-C with no
washers?
The difference is the "arc" of the camber change as the suspension is
compressed. When you fully compress the suspension these two setups may
be at the same total negative camber, so it may seem that they are
providing the same camber change result. The longer the camber link is,
the more "Linear" the arc of the camber change is going to be. For
example, if you put 1-C with no washers on your car and then set the
camber at 0 degrees at ride height, then slowly push the rear end down,
the negative camber will progressively increase at a steady or linear
rate. If you put 1-B with 3 washers on your car and then set the camber
at 0 degrees at ride height, then slowly push he rear end down, there
will be a "Dead" spot where the camber will not change as you push it
down, then aggressively change at the end of the suspension
compression. Now the handling differnece between these two setups can
be felt in the form of inconsistency.
The speed at which you enter the
corner will magnify the differences. The 1-C no washer will have the
same side bite no matter how fast or slow you enter the corner. The 1-B
three washer setup will be speed sensitive and have not enough side
bite if you go too slow or too much side bite if you go too fast.
Everything is a give and a take you may like the way the 1-C feels
because it is consistent but it may not produce the maximum amount of
corner speed that a 1-B setup may give you, even if it may be harder to
drive.
***
Zero degrees of antisquat "Frees Up" the rear end On Power and it also
gives you a little more side bite. I like to start with the minimum
amount of Antisquat because it gives the rear end the most balanced
amount of traction as you enter and exit the corner. It also minimizes
wheelies, which are cool to watch, but waste time.
The only time that I
increase the Antisquat is if I am on a smooth surface track that has
limited traction. If I am on a ruff track I always run 0 as it makes it
easier for the suspension to soak up the bumps and ruts.
The amount of Antisquat you use depends on the track conditions. If the
track is very smooth, more antisquat will give you more forward
traction. If the track is bumpy or rutty more antisquat will give you
less forward traction.
***
Changing the steering link hole position in the steering rack (From
front to back), with out changing the spindles to the inline version,
will change the amount of Ackerman the front tires have when turned.
Ackerman is the front tire angle difference when the tires are fully
turned to the right or left. For example, if your car has no Ackerman,
when the steering is fully turned both front tires will be at the same
45 degree angle. If you add Ackerman, the inside tire (the one closest
to the apex of the turn) will be at an increased angle compared to the
opposite front tire. For example, if you turn the front wheels fully to
the right, the right tire will be at a 45 degree angle and the left
tire will be at a 30 degree angle. This difference in front tire angle
is called Ackerman.
Increasing Ackerman will tame the steering down and give you better
high speed sweeper steering. Decreasing Ackerman will make the steering
more aggressive high speed steering and give you better low speed 180
degree corner steering. So using the "Back" steering rack position will
make your car a little easier to drive because it will tame down the
steering, but it may also tame it down too much and make you too slow
in the corners. I like a lot of steering in my cars so I only use the
front steering rack position.
***
The "Spindles" are what your front tires attach to. You can change the
height of the spindle and this mainly changes your corner exiting
steering. If you need more steering as you exit the corner, you can
raise the spindles (Two washers on the bottom). If you need less
steering as you exit the corner, you can lower the spindles (Two
washers on the top). Just make sure that you add or remove bump
steering spacers as you raise or lower the spindles. This will keep
your bump steer the same.
***
If you are running on the inside hole of the rear A-arm a # 1 piston
does not have enough "Pack". This causes the rear end to bottom out
easily and perform a nice Slap Bounce routine that Scott Hamilton would
envy. You need to run at least a #2 piston with 25wt AE oil. If your
track has large jumps and you are landing flat after a four or five
feet of air time you will need a lot of “Pack” to absorb the landing.
So a #3 piston with 20wt or 25wt oil will be ideal for that situation.
Pack can be your enemy though if the track is rutty. Too much Pack on a
rutty track will cause your car to be very unpredictable in the rough
stuff.
***
A softer front spring will give you less corner entering steering and
more corner exiting steering.
It is all about tire pressure.
As you enter the corner your chassis leans opposite of the corner
direction, which transfers more weight to the outside front tire. Now
based on the spring rate, the shock / spring has one of two choices.
(1)
Resist the chass is lean and transfer the weight to the tire. This
gives you more tire pressure and thus more friction with the racing
surface = more entering steering.
(2) Absorbe the chassis lean and
lower the ride height. This gives you less tire pressure and thus less
friction with the racing surface. But since the front ride height is
lower you gain exiting steering becuase there is more weight transfered
to the front end = more exiting steering.
