Whether you're cruising the streets, cutting apexes on a road course, or taking it to the drag strip, you might have considered fitting a rollcage or bar in your car. After weighing the cost versus benefit for our Mk4 GTI project car, we decided to fit a roll bar with the guidance of safety experts, Autopower Industries.
There are three advantages to adding a rollcage or bar. First, either can improve your safety in the event of a rollover. Second, the increased structural rigidity creates a stiffer, more responsive chassis - according to Autopower, the more mounting points a bar has, the stiffer the chassis will be. Third, there's also a visual factor. Many car builders model their projects on motorsport themes. Just as aftermarket aerodynamic improvements can improve form and function, the safety of a roll bar can also look just as good as it performs.
Options And Goals
Autopower offers several products for old and new Euros, from the BMW E30 to Mini Cooper and even the Saab 9000. While different combinations are available depending on the vehicle, the Mk4 GTI has three types of roll bars: Street, Street-Sport and Race, as well as a full, bolt-in rollcage.
The Street bar is the basic roll bar, which mounts at four points near the B-pillars and rear fenders, bridged across the roofline. The Street-Sport adds a horizontal cross bar to mount racing harnesses or a seat-collapse bracket for added safety. The Race version goes one step further and includes a diagonal cross bar for lateral strength.
Generally, a roll bar is mounted behind the driver, whereas a rollcage is attached at six points, the A-, B- and C-pillars. As a result, a cage can interfere with entry as you step over some tubes and watch your head on others. In addition to lost interior space, Autopower explained race harnesses are needed to keep occupants away from possible injury. Although a cage would be optimal for a dedicated weekend warrior, it's overkill for daily driving and could actually contribute to injuries in a street accident if harnesses aren't worn correctly.
While our GTI is mostly assigned daily driver duties, it also sees several shows each season and will eventually get track time. With these goals in mind, Autopower cautioned a cage would rob interior space, not to mention the inherent danger of a cage without proper harnesses.
After studying the facts, we made a concession to civility and decided a roll bar like the Street-Sport version was the best solution. When mounted, it would provide considerable rollover protection without the repercussions of a cage, while only increasing weight by a minimal 30 lb. Furthermore, driver vision isn't affected, as compared to a cage or the Race bar.
Design In Mind
The design of Autopower bars is based on SCCA and NASA road racing spec. The manufacturer works closely with these bodies to offer products that pass tech inspections, although our half-cage isn't compliant with some professional regs.
All bars and cages are designed to work with factory interiors. By cutting four or six mounting holes, the interior can be kept in every application.
Another advantage of Autopower's bars is the bolt-in technology that doesn't require welding; amateur mechanics can install them at home. Bolt-ins also have the ability to be removed if necessary, unlike weld-in units.
The paint on each bar is limited to black enamel. Black doesn't draw too much attention and while it's unfortunate they don't offer custom paints or finishes, each bar is coated in-house.
The bars are manufactured from 1.75x0.120" DOM-classified seamless mild steel. This is stronger than some roll bars made of electric resistance welded steel (ERW). DOM-classified steel has fewer imperfections and tubing can be smaller than ERW.
Driver Beware
With either a roll bar or cage, there's a major risk of occupants hitting their head on the bar in the event of an accident. The risk is lessened with the half-cage because it sits behind the driver; however, it's still recommended to wrap proper padding around the bars for protection. Transporting rear passengers with a roll bar is highly discouraged. Not only is it harder to access the back, but is extremely dangerous if a person were to hit the bars in an accident.