By Dev Clough
Upshifting
Upshifting should be done smoothly. Speedshifting will
shorten the gearbox life. The only time I force an upshift is in
a side by side race to the next corner, for position. I will sometimes
bang a gear in an effort to take or hold a position.
Listen to the in-car shifts of professional racers on TV, and they
rarely bang shifts. Upshifts are done quickly and smoothly, but
are not forced. If you want your gearbox to have a long, happy life,
feel the gears, the changes should fall in, without being forced.
Downshifting
The first thing to understand is the purpose of the downshift. It
is not to slow the car, that is the job of the brakes. The purpose
of downshifting is to have the car in the correct gear to accelerate
through and out of the corner.
Here is the process:
As you enter the braking zone, apply the brakes, but do not immediately
downshift. The downshift should be done after the RPMs have
dropped, but must be complete before you begin the turn-in. Downshifting
too early can over-rev the motor, waiting too long means you will
be rolling the car through the corner entry, giving up the ability
to use the throttle to balance the car.
Heel toe Downshifting
Why is Heel toe important? Remember, as you approach
the traction limit of your tires, anything that takes traction can
cause the car to slide. Have you ever downshifted and released the
clutch too quickly and felt the car jump as the engine RPMs
were forced up to match the cars speed? Kind of like tapping the
brakes. Think of this, if you are driving at 70 mph in 4th gear,
at 4000 rpms and shift down to 3rd, your engine rpms
will go up, to say 5200 rpms. You can accomplish this by easing
out the clutch, until the engine is forced up in rpms by the
car. This works, but it is slow, hard on the clutch and transmission
synchros, and uses up some of your traction to force the RPMs
up. The alternative is to match the engine speed to the transmission
speed (in the lower gear). This can be done by pushing in the clutch,
blipping the throttle, selecting the lower gear and releasing the
clutch. The problem is, downshifting is done at the same time we
are braking. Guess what, we have two feet and three pedals to operate
simultaneously! The Heel Toe technique solves this problem.
Heel toe is a misnomer. It can be done in many ways,
depending on the pedals in the car, and the anatomy of the driver.
Although it can be, it is not usually done with the heel and toe.
The process is commonly done by placing the ball of the foot on
the right side of the brake pedal, and while holding consistent
brake pressure, the side of the foot rolls onto the throttle, blipping
the throttle. Depending on your anatomy, and the pedals, it can
be done any way that allows the brakes to be used while the throttle
is blipped.
Heel Toe cannot be done smoothly unless two things are done:
1) The pedals must be matched. Normally this is done by adjusting
until the brake and throttle are even in height, when the brakes
are pressed on. The pedals must also be properly spaced. In my car
it required adjusting and bending the gas pedal until I got the
match I needed. In many cars, the pedals have some range of adjustment,
making the process easier. One thing to remember, as you adjust
the gas pedal, make sure that there is a mechanical stop for the
pedal. If you rely on the stops in the carburetor or injection system
to stop the motion, you will probably bend or break something as
you try to squeeze a couple more horsepower out of the pedal. Also,
make sure the linkage allows the butterflies in the carburetor to
be fully open when the pedal hits your mechanical stop.
2) The technique must be practiced. Do not come to the track, with
the intention of learning to Heel Toe. Learn the technique on the
street, and practice it until it is second nature, before trying
it at the track. If your street car is different from your track
car, and your street car has a manual transmission, set its pedals
for Heel Toe, and learn the technique. Try to get the pedal arrangement
similar for both cars. If you must learn the technique in your track
car, make it low on your priority list. When driving the line is
second nature, you are comfortable in traffic, youve got all
of the corner stations figured out, start working on it.
Heel Toe is not a required skill at your first event or two, as
a matter of fact, you dont ever have to learn it. It is a
tool that will make you a smoother driver (ie. faster!), and you
will be easier on your equipment. Its a tool to add to your
arsenal of skills as your high performance driving becomes more
polished.
|