Many consider sanction-mandated roll cage construction as a tedious chore, until one day when it may save your bacon. On that possible day something causes you and your car to tangle with anything from the guardwall to a dreaded “roof ride,” that cage will immediately become your best friend.
To say that S&W Race Cars are experts at developing and selling pre-engineered roll cage kits is an understatement. With over 2,800 kits available for your specific body style, we talked to the team there as they developed yet another cage kit to offer.
John Burke, an engineer at S&W explains, “When we can get a car into the shop to develop a new kit, we go through a very stringent measuring process. Even if we don’t offer a cage kit yet for your body style, we have a custom measurement form that customers can complete for a custom cage.
Burk describes the measuring process as being very involved. An S&W cage design achieves a proper fit and allows the customer to easily install through the door openings or within the rear deck area into the trunk.
S&W offers weld-in cage kit choices from four-point street bars, eight-point roll bars, to 10-point roll cages. Each design has its place, depending on the racing sanction rules related to the speed of your car. S&W offers cage conversion kits that expand an eight-point roll bar set into a 10-point cage, if you have stepped up your game. You can even add a funny car driver’s surround with your existing cage with an S&W kit.
The only way an actual cage kit is added to our part numbers is if we do our own measuring process. We do not rely on customers’ measurement to create a mass-produced cage kit. – John Burke
“When looking for the optimum places to mount the cage onto the floor pan, it is very involved to find the best access and strongest mounting points,” Burke adds. “We don’t want to rip the carpet out to measure the floor pan, but if you take a concentrated look under the car, you can develop the flattest area for mounting roll cage floor plates.”
Burke will analyze how the rocker box is formed and how it mates to the floor. Cage pads will either sit on top of the rocker box or just inside on top of the floor pan. He explains that most of the time, it’s going to sit on the floor pan just inside the rocker box to clear a vehicle’s doors when closed.
“We then carefully consider the trunk area and design the back bars. We have custom tools that make measuring simpler and more precise,” Burke says. “Some complexity comes into play around the dashboard area or clearances to reinstall the factory seats that can be bulky.”
Cage kits can be constructed with a choice of EWS, DOM, or chromoly tubing. Sanction rules are the most obvious deciding factor. The two main choices for all-out racing at the strip are DOM (mild steel) and chromoly tubing.
DOM tubing stands for “drawn over mandrel,” as the tubing is formed for strength and more accurate diameter and thickness. DOM tubing must have thicker walls than chromoly, to offer equal strength and pass the same chassis rule requirement. That means mild steel tubing is the heavier alternative, but cheaper. That old “speed costs money” adage again comes into play, this time with the roll cage.
“The do-it-yourselfer needs to know what their sanction rules expect,” Burke cautions. “We have great people here who will help you on the phone concerning your cage choices matched to your motorsport.”
Another tip when choosing a roll bar or cage kit is to be extremely self-critical of your welding experience. Even if you can perform the careful cutting, “fish mouthing,” and completely tack weld the cage, don’t be too proud to get an experienced friend or local shop to complete the finish welds.
When installing the cage, keep in mind that you must weld all joints completely around, especially in the area where the cage is near the roof. In their instructions, S&W offers a great idea to tack the cage together, cut holes in the floor, and drop the cage through the floor. Then you can completely and comfortably weld the top joints along the roof hoop, raise the cage and mount onto your cage pads.
Protecting yourself with a proper roll cage kit is not the place to take shortcuts, nor will the tech inspector allow it. Take a stroll through the staging lanes and look at the precise fitment and welds that make up an integral part of the race cars. A strong cage may improve your chassis flex and performance, but also is paramount to your protection.