2001
Chevrolet Corvette Restoration Kit
the current
flow through the solenoid. The solenoid adjusts the amount
of
power steering assist
in
order to
achieve a given
level
of
driver effort to turn the vehicle.
Magna Steer
accomplishes this by adding or subtracting torque
on
the rotary input shaft to the power rack
and pinion. The amount
of
steering assist
is
dependent upon vehicle speed. As the vehicle speed
increases, the following actions occur:
• The steering assist decreases.
• The driver effort increases.
As the
vehicle speed decreases, the following actions occur:
• The steering assist increases.
• The driver effort decreases.
The scan
tool can
be
used to adjust the amount
of
steering assist if the customer requests. The steering
assist has 3 settings:
• Factory calibration
•
More firm
• Less firm
Variable Effort Steering Components
The MAGNASTEER® system consists
of
the following components:
• The electronic brake control module (EBCM).
• The MAGNASTEER® actuator
• The power rack gear
• The power steering pump
The Electronic Brake Control Module (EBCM)
Refer to ABS Description.
The MAGNASTEER® Actuator
The MAGNASTEER®
is
an integral part
of
the power steering gear. The MAGNASTEER® actuator
consists
of
the following components:
• A rotary valve
•
A permanent magnet that
is
attached to the input shaft
of
the rotary valve
•
Two pole pieces that are attached to the output side
of
the valve (the pinion)
• An electromagnetic coil mounted
in
the gear housing
When the
coil
is
energized, a magnetic field
is
formed between the permanent magnet and the pole
pieces, which increases the torque
on
the input shaft to the steering gear. The EBCM controls the current
flow to the coil. As the vehicle speed increases, the EBCM increases the current flow. The increased
current
flow results
in
an increase
in
steering effort.
Other power steering system components, while specially modified for use with MAGNASTEER®, are
similar to non-MAGNASTEER® power steering components.
The Power Rack Gear
The design
of
the MAGNASTEER® power rack and pinion assembly
is
the same for a non-
MAGNASTEER® system except for
valve machining differences. The steering wheel movement transfers
to the pinion. The pinion moves the rack
left or right by meshing the pinion and rack teeth. The force
transmits through the tie rod ends and the steering
knuckles to turn the wheels.
The power rack and pinion steering system has a rotary control valve. The rotary control valve directs
hydraulic fluid from the power steering pump to the two sides
of
the rack piston. The piston attaches to
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