This particular system is named after the kind of gears that are used. A little pinion gear, connected to the steering wheel, meshes with a long rack gear, connected at both ends to the tie rods and steering knuckles. When the driver turns the tyre, it pushes the rack remaining or right, thereby turning the wheels left or right.
A FRESH Rack and Pinion In a car Restoration ProjectFor decades, the typical power-steering system has been hydraulically assisted. A hydraulic pump, the power-steering pump, uses engine capacity to generate hydraulic pressure, which is certainly fed through the power steering hoses to the rack. When steering is usually used, hydraulic pressure improves the driver’s input force, making for simpler steering.
Rack-and-pinion steering is somewhat different from the steering boxes we viewed in last month’s issue. Possibly the best way to describe it is that it combines the steering box and tie rod, or centerlink, into one device. It also mounts up front, across the car, either behind the axle rack pinion steering china centerline or before it. This is why you’ll hear steering racks referred to as frontsteer and rear-steer racks. Mount a rear-steer unit in front of the axle centerline and the tires will go still left when you steer right, in exactly the same way some steering boxes have to have their internals reversed to work in certain situations.
The tyre, through the steering column, is directly linked to the rack, though it may also employ universal joints, a rag joint, or a sliding joint. In the rack is a pinion assembly that subsequently movements a toothed piston, and this operates the steering gear. The tie rods are connected to each end of the piston.
The advantage of rack-and-pinion steering is that it’s more precise than a steering box. There are fewer shifting parts, which makes the steering more responsive. Of course, as with boxes, there will be the options of manual or power steering. It’s also extremely easy to mess up your frontend geometry when adding a steering rack to an existing frontend, leading to bumpsteer, though of training course this will be eliminated if you opt for one of the many rack-and-pinion retrofit kits we’ll go into shortly.
The steering equipment transfers Rack and Pinionthe rotary movement of the steering wheel to a linear motion used to steer the front wheels. Two types of steering gear are used today, the typical gear package and the rack and pinion. The standard gear box uses a worm gear that is rotated by the steering wheel to move the pitman shaft. The worm equipment includes spiral cut grooves 
that mesh with a sector gear near the top of the pitman shaft. The spiral actions of the worm equipment causes the pitman shaft to move the steering linkage in a linear motion. Power steering is achieved by using hydraulic pressure to assist in the rotation of the worm equipment.