NASCAR reaffirmes rear suspension rules

mmie Johnson, driver of the #48 Lowe's Chevrolet, drives during practice for the NASCAR Sprint Cup Series Federated Auto Parts 400 at Richmond International Raceway on September 7, 2012 in Richmond, Virginia. (Photo by Chris Graythen/Getty Images)
mmie Johnson, driver of the #48 Lowe’s Chevrolet, drives during practice for the NASCAR Sprint Cup Series Federated Auto Parts 400 at Richmond International Raceway on September 7, 2012 in Richmond, Virginia. (Photo by Chris Graythen/Getty Images)

RICHMOND, Va. — NASCAR views the technical bulletin issued to Cup teams this week as reaffirming existing rules regarding setup of the rear suspensions, but it does limit the amount of finagling crew chiefs can do with the truck trailing arm front mounting bushing assemblies.

If that techno-speak seems hopelessly arcane, NASCAR is making sure crew chiefs understand the limits, direction and freedom of “travel” or movement in the rear suspension that’s allowed under existing rules.

The bottom line is that rear-axle steering improves the aerodynamic properties of the Cup cars and allows them to turn more easily through the corners. The bulletin specifies a quarter-inch of travel in one direction only, and the assemblies in question must move freely through that quarter-inch of travel (as opposed to locking in position, for example).

With Hendrick Motorsports at the vanguard, Cup teams have been working hard to maximize the aerodynamic advantages of rear suspension setups.

“This doesn’t change any rules that we’ve already had,” said Cup series director John Darby. “It reconfirms how far teams can go with their rear suspension setups. Teams have found that, with a car’s rear-axle steer, more is better as it helps with aero and gets the cars through the corners faster.

“We are just reminding the teams what the limitations are and that they cannot go past these limitations.”

Five-time champion Jimmie Johnson didn’t appear concerned about the bulletin.

“I think NASCAR made it known that they are just putting parameters on what’s going on,” Johnson said. “There is no change.”

About Greg Engle 7420 Articles
Greg is a published award winning sportswriter who spent 23 years combined active and active reserve military service, much of that in and around the Special Operations community. Greg is the author of "The Nuts and Bolts of NASCAR: The Definitive Viewers' Guide to Big-Time Stock Car Auto Racing" and has been published in major publications across the country including the Los Angeles Times, the Cleveland Plain Dealer and the Atlanta Journal-Constitution. He was also a contributor to Chicken Soup for the NASCAR Soul, published in 2010, and the Christmas edition in 2016. He wrote as the NASCAR, Formula 1, Auto Reviews and National Veterans Affairs Examiner for Examiner.com and has appeared on Fox News. He holds a BS degree in communications, a Masters degree in psychology and is currently a PhD candidate majoring in psychology. He is currently the weekend Motorsports Editor for Autoweek.