When JBL Motorsports began designing this car, the engineering brief was to build a classic roadster that would provide a competitive edge in various types of racing/road situations while insuring the highest quality construction and the utilization of the finest components available in the racing industry. As an integral part of the design process, there were some basic goals.
1. Produce a very
stiff (minimum 24 HZ frequency) chassis with torsional numbers above 4500 lbs per degree.
2. Optimize the wheelbase to track ratios, the CG height and location, the Roll axis, as well as minimize the polar moment to reduce the yaw characteristics normally found in a front engine/rear drive chassis. (In other words, make the chassis behave as a mid-engine design.)
3. Produce suspension camber curves optimized for current radial tire construction, eliminating the need for excessive static negative camber angles as seen on most roadsters for track use. (This allows optimum slip angle generation, but greatly reduces tire wear and yields very even tire temperatures.)
4. Allow wheel rates in the 175 pound range to insure suspension compliance on rough surfaces (Maintain tire contact patch) and to provide for a pleasant ride for street use.
5. Provide driver aids, such as cockpit adjustable anti-roll bars and brake bias adjustment to allow for changing track and road conditions.
6. The design specifications must insure that all components are the highest quality available and that all critical components of the chassis be built in-house. For example, all chassis tubes and panels are machined on CNC mills and CNC sheet metal cutters. All attachment points (Pickup points, cross members, engine mounts, seat belt mounts, etc.) in the chassis are through inserts tig welded into the tubes. All suspension parts, such as A-arms, rockers, front uprights, anti-roll bars, their mounts, and blades are all produced in-house on state of the art CNC machinery.
7. The bodywork must capture the essence of the 60's roadster style, but allow for improved aerodynamics and packaging of the driver and mechanical components. In other words, if you were to build one today, it would look like the JBL. These design goals have produced a chassis that has shown through its performance and reliability to be a superior package for track and road usage.