- AUTOMATED
SHIFTERS
One of the most effective
products you can use to improve the consistency of your car is an automated
shifter. Shifts are made at exactly the same point in every run, which eliminates
one of the major variables effecting the E.T. of the car. While
automated shifting improves all cars, two types of cars respond particularly
well: heavy cars with low/medium power and light cars with high power.
- Low
/ medium horsepower engines
need the transmissions' gear multiplication to accelerate heavy cars. Shifting
to high gear removes the multiplication, greatly affecting the engines ability
to move the car.
- High
powered engines usually have a peaky torque curve and run through
low gear quickly when installed in light cars.
- Shifting early or
late ends up with the engine being far away from the desired torque range
at the shift point. In both cases, it's easy to see that a slight change
in the shift RPM makes a big change in the car's acceleration rate which
causes an even bigger change in the E.T.
- Safety plays a role
also, particularly with high horsepower cars.
An automated shifter allows the driver to grab the steering wheel with both
hands and concentrate on keeping the car straight during a run. A straight
run is safer and more consistent.
- There
are two ways to control the shift point of the car:
- The
first is the tried and proven method of using an RPM2
switch module. This switch module determines the engine RPM by reading
the pulses given off by the ignition system. These are the same pulses that
are used by the tachometer. When the engine reaches the RPM that has been
set in the RPM switch, the RPM switch activates your air or electric shifter.
- The
second method is to use our "Shift
Timer". The Shift Timer is a device that starts timing when the
transbrake is released and at the preset time, activates your air or electric
shifter.
- The
Shift Timer works particularly well in cars
that have "loose" converters.
- The engine in a
car with a "loose" converter tends to run at a fixed speed until
the converter locks up and stops slipping.
- Since the engine
runs in a narrow rpm band near the intended shift point for a large portion
of the run, the actual shift point can vary widely.
- The Shift Timer
will allow the car to shift at a precise point during a run and the engine
rpm doesn't matter.
- Another
situation where the timer works well is on throttle
stop timer equipped cars because the shift can be positioned in accordance
with the throttle stop timing.
- Shifting while the
engine is in the "stopped" condition greatly reduces the chance
of tire spin when the engine goes back to wide open throttle again.
- To
actually shift the car, two types of automated shifters
are available, CO2 or electric.
Both work equally well and are a matter of driver preference. The "shifter
and accessories" section explains the advantages of each type.
