Cages & Roll Bars
First and foremost roll bars and roll cages are designed to help protect the vehicle occupants from injury in the event an accident. This is the first line of defense. The roll bar/cage design is generally determined and limited by the rules that govern the vehicle class. The SECONDARY function is chassis rigidity. Never sacrifice your safety for the sake of rigidity.
Roll Bars typically have 4 points. This simply means the bar attaches to the chassis at 4 structural points. They consist of a main hoop, harness bar and at least two rear bars. Most have a diagonal bar within the main hoop to offer lateral support in the event of a rollover. Roll bars are a good option for the dual purpose track day car and are mandatory when tracking any convertible.
How Do Our Cages Hold Up?
Watch for yourself. This is the second EVO chassis Piper Motorsport built for this customer. After a left front tire failure, the driver loses control and shoots off the track. The initial impact into the barrier was recorded at 86 mph. The car flips violently and cartwheels until it comes to a stop on all 4’s. This was a brutal crash. Thankfully our client was unharmed and was able to exit the vehicle without issue as you can see from the video. He only suffered minor bruising from the impact. Again, we are very thankful he was able to walk away. We stress, do not take safety lightly. These are great reminders that though racing is fun, it can also be deadly. It happens fast and unexpectedly. Prepare for the worst!
Welding – Fabrication – Design
Dependent upon which material is selected for the cage is the welding technique. TIG and MIG welding are the accepted methods. Each has minimal pros and cons but when executed properly, equally strong.
When fabricating a cage, it is recommended to remove all interior unless otherwise stated by your class rules (showroom stock etc.). To start, we determine where the main hoop and harness bar should be located. This is done by sitting the driver and the seat of choice in the car to determine and measure their seating position. The harness and head restraint selected will also help us determine the harness bar height and location. We then determine the base plate locations on the chassis. Base plates serve as mounting points and have more surface area that gives the cage a rigid platform to stand. The base plate locations are carefully chosen to utilize the stronger sections of the chassis to best support the cage. Once we’ve determined the main hoop and base plate locations the roll cage construction begins.