How Does Rack and Pinion Steering Work?
Automotive engineering has come a long way since the old days. Everything has continued to evolve - becoming more efficient, more powerful, better looking and impacting the lives of millions of people all over the world. Most of the time, when you read about the latest greatest engineering feat, it involves something exciting. However, some of the most important advances to our cars and trucks are the simple stuff, the not-so-exciting bits and pieces that make up your daily driver or your favorite weekend warrior.
Rack and pinion steering are a specific type of steering design that uses a set of gears to convert rotational motion (steering wheel input) into linear motion (wheels turning right or left). This style of steering essentially eliminated cross-style steering systems that use a combination of arms connected to the steering knuckle or spindle to move the vehicle left or right. If you have ever found yourself behind the wheel of an old farm truck or classic car, you have probably noticed just how difficult it can be to turn the wheel, which can lead to some pretty scary moments while driving.
Rack and pinion steering provide a much better driver feel when turning. It takes far less effort to turn your vehicle left or right, which increases driver confidence and feel in their vehicle. Racks are built with various different ratios or gear reductions. Essentially, they use different sized gears to shorten or lengthen the number of revolutions on the steering wheel it takes to go lock-to-lock on the wheel end. This comes in handy in various racing applications, because a driver can use very little movement to steer one way or the other, allowing for incredibly precise, small adjustments to drive and steer their race car. In the confined spaces of a race car cockpit, this could be the difference between executing a perfect slide job or running it up into the concrete barrier.
Rack and pinion steering can also be powered. In the hot rod world, we tend to still see both styles: manual and powered. Manual racks are still being used because they are incredibly versatile, simple, and easy to install. The manual rack can handle the smaller, lighter front end load that traditional hot rods encompass. Luckily, if you find that a manual rack is just too much work or feels too archaic, power-assisted rack and pinions are even more common. With the help of hydraulic assistance, the same rack and pinion system is even easier to get things turning. A hydraulic pump feeds pressurized fluid into the body of your rack and pinion, moving a piston left or right, which once attached to your spindle (steering knuckle), moves your car left or right.
Nearly every late model car and truck from the last 40 or so years, has been using power rack and pinion steering systems. This technology just worked - it was cheap to design and manufacture, easy to understand and work on, as well as it being a versatile design that could be used in nearly any chassis or suspension setup. Eventually, racers and rodders adopted this OE technology into their own cars and trucks to make their cars easier to drive and race, as well as work on when the time came for maintenance. In our world, rodders and racers alike, want things to work properly, be easy to install and maintain, and not cost an arm or leg. Power rack and pinions fill all those needs and have for a very long time.
With time, things will change. We have already started to see a slight variation of this steering system as of recently, with the OEM's trying out electronically power assisted rack and pinions - but to be honest, they haven’t strayed from the actual steering design, just how it is powered. It is safe to say that rack and pinion technology changed the automotive world for good and in a big way - it just is something that doesn’t get the attention it deserves. It made all of our lives easier, safer, and more cost effective to own and maintain whatever you drive. Who knows, maybe someone reading this will set out on their own automotive engineering journey and discover a new way to change all of our lives once again.