Created with Sketch. Created with Sketch.

Whats does the sway bar do on your MINI?

Whats does the sway bar do on your MINI?  


When it comes to sway bars (also known as anti-roll bars, stabilizer bars), the common misconception is that their sole purpose is to keep the body of the vehicle from rolling to one side during a tight turn. While that is true, sway bars do more for your car’s handling than you might think.

When a vehicle has excessive body roll, the majority of its weight is shifted to the outer tires during a turn, causing less weight to sit on the inner tires. Lateral grip is something you don’t want to sacrifice on the twisties or a racetrack and a sway bar’s purpose is to keep suspension movements relative throughout the turns. This means that when the vehicle makes a right turn, the left side of the vehicle’s suspension will compress similarly to the right side, keeping more weight on the inner tires.

Simply put, a sway bar is a torsional spring that connects to both the left and right sides of the suspension to reduce body roll, as Oliver Rathlein of Eibach explained, “The sway bar links both sides of the suspension system to help reduce body roll when cornering. When both wheels take a bump equally, the wheels move the same amount without twisting the anti-roll bar. Individual wheel movement or body roll will force the bar to twist as the lever arms are moved, thereby adding the bar’s own spring rate to that of the car’s springs. Although an anti-roll bar’s main function is to reduce body roll in cornering, it also influences overall handling. You can fine-tune Over- or Understeering with them.”

Besides the performance associated with not having as much body roll, sway bars also improve the weight distribution amongst all four tires. “Since you are cornering flatter, less weight is being transferred to the outside tire,” explained Ben Knaus of Hellwig Products. “Because of this, you can go faster around a corner before losing traction, which means faster and safer cornering.”

For the hobbyist driver, racer or track day enthusiast, aftermarket sway bars are a crucial aspect of the car’s handling. Like Rathlein said earlier, you can fine-tune for over or understeering tendencies. To fine-tune, one needs to first find a sway bar compatible with his or her car in the right diameter and that’s where Sneed4Speed comes in for the MINI Cooper Community.  With over a decade of MINI racing experience, they have done already done the R&D to figure out which sway bar diameter works with which tires and spring rates.  “We have found the 19mm rear bar works best for most drivers who don’t regularly track their cars” said Chris Sneed, founder of Sneed4Speed.  “All our bars can be adjusted in their 3 mounting holes to fine tune to the driver preference but we have found most drivers like the 19mm bar in the middle or hard holes.  It gives an awesome increase in corning speed without a noticeable increase in ride stiffness.  The 22mm and 24mm bars are better for the guys tracking and racing, running stickier tires and not worried about the street ride quality as much but you can still drive these bars on the street everyday if you want.”