Installing a rear sway bar
Time: 1 hour
Tools: standard socket set, standard wrenches
Tinware: rear sway bar, sway bar mounting kit (includes bolts, washers, and necessary spacers)
Tip: Always be patient and take your time when measuring pieces for drilling. The correctly achieved results are well worth the extra steps.
Performance gains: a solid, well-planted rear suspension that works in unison with your front-end components
The rear sway bar is an often-overlooked piece of the rear suspension. Perhaps it’s due to the fact that most of these cars were built and sold sans rear anti-roll (sway) bar. Back in those days, only the special high performance vehicles were granted additional rear reinforcements. Even a large number of Chevrolet’s factory Super Sports did not have a rear sway bar. The reason? The factory was interested mainly in production and keeping all costs as low as possible. Since many manufacturers inside General Motors shared the same or similar platforms (not to mention parts), it made more sense to utilize the “parts bin” availability from each other than to make each rear end assembly different. And as we all know, the vast majority of assembly line cars at the time were not performance vehicles. Instead, they were practical and compromised to meet the everyday needs of the consumer. Truth be told, most car buyers were not interested in the performance arena, or plainly could not afford it. Therefore millions of folks opted for the underpowered family sedans, station wagons, and six cylinder grocery getters.
And what are we getting at? Simple. When used in any high performance application, the poor geometry and flexibility of the stock rear suspension needs work. In addition to control arms and bushings, the rear sway bar is one of the first improvements that comes to mind. And by far, it has to be the easiest as well.
If your car was not originally equipped with a rear sway bar, chances are you will need to drill two holes in the sides of your existing lower control arms to properly mount the bar. This is an important step. Making sure you have marked the arms to be drilled evenly and symmetrically is key. If your measurements are even slightly out of whack, it can affect and hurt your car’s performance. Don’t take any chances– double check your work!
The easiest way to obtain the correct placement of the sway bar mounting holes is to measure a pair of pre-drilled factory lower control arms. This will ensure the accuracy needed to rightfully pull off the job. However, if you are unable to use a factory template, this can be done by simply and carefully measuring the distance from the forward end of the control arm to the location of the sway bar. Have a friend or two help you out with the mock-up. Once its position is determined, remove the arms from the vehicle and place them on the workbench. Scribe a mark in the same location on each arm representing the sway bar. Secondly, transfer the hole pattern of the sway bar to each control arm. Now you are ready to drill!
The sway bar mounting kit comes complete with hardware and spacers for non-boxed control arms. The bolts supplied are typically 3/8”, so make your holes accordingly. If at all possible, we strongly recommend using a drill press to punch out the control arms. Your holes will come out clean and straight every time. If not, use a hefty power drill and be careful. When drilling larger diameter holes, always use a centerpunch and a smaller pilot drill bit first before reaming the final size. This will keep the larger drill bit from “walking” out of position on the surface and throwing off your placement.
In this photo, we show the sway bar bolting right up to a fully-boxed control arm. If you use a stock (unboxed) control arm, the supplied spacers would fit right inside the arm adding strength and rigidity.
Now we are ready for the install. With the lower control arms bolted back in place, lift the sway bar to meet its newfound mounting holes. The spacers that come in the mounting kit actually belong inside the lower control arm. This is to prevent excess load or stress on the sidewall of the arm while tightening the nuts and bolts.