Have you ever asked yourself just how much work goes into build-ing a serious time attack machine? We aren’t talking about bolting on parts from a tuning catalog, but a full-on, top-spec professional project. The car you see here is the perfect example of such a build, and this is the first time this car has graced the pages of any magazine. We teamed up with the guys at Tomei, Cusco, and Voltex to bring you an insight on how this new Team Tarzan Time Attack GDB Impreza has come to be.
It all started last year when Eiji Yamada, aka Tarzan, approached Tomei about teaming up together to create an all-new time attack car. Having been involved in the Japanese time attack scene for years, Tarzan decided this new ride would be specifically built to compete here in the U.S. in both the Redline and Superlap Series. Think of it as a new challenge, something he wanted to approach with full backup from the best Japanese companies. It wasn’t long before Cusco and Voltex came on board, as well as Hankook on the tire front, and the result is nothing short of stunning.
Late last year the build got underway. Tomei sourced a bare GDB Impreza shell and sent it to Cusco where the transformation began. The same guys involved in creating the Super GT300 Impreza where let loose with spot welders, as well as fabricating additional bracing for critical areas. With experience in building a GT car, these guys knew exactly what to do and made sure the whole chassis would be incredibly stiff. A race-spec rollcage was constructed and welded, further helping in the rigidity department, as well as making sure Tarzan is kept safe in case of an accident. At this point the Pianetto air jacks were fitted into position, two at the front and curiously only one centrally mounted at the rear. This was probably done to avoid adding unnecessary weight. A lot of work went into stiffening the front and rear suspension turrets, and modifying the actual wheel arches to accommodate the wider track and bigger wheels. As the chassis prep was being completed the Cusco engineers began looking at the front and rear suspension layout. They decided that for this particular application the stock Subaru Impreza arms and geometry just wouldn’t do, so the whole lot was scrapped. Joining the specially set up, Cusco Comp-X adjustable dampers is a series of custom-built links, all connected up to the one-off front and rear hubs. Even the steering knuckles are adjustable and attach to the lower section of the front hubs through custom pivots.
Having pillow-ball connection on each of the lower arms allows for limitless geometry adjustability, and having reengineered everything has allowed the whole roll center to be lower than it would be on a stock car. This greatly improves overall handling balance as well as getting the most out of the increased track and sticky Hankook Ventus Z214 275/35-18 tires. At the rear, it is much the same story with adjustable lower links and tension rods bolted onto the lower part of the custom hubs. Beefy Cusco antiroll bars are used front and rear. At this point it was the turn of the brakes and again, like what we have seen so far, no compromises were made. Straight from the Brembo competition catalog are the eight-pot forged front calipers mated to two-piece slotted rotors. These calipers help keep un-sprung weight to a minimum thanks to their light construction, which also feature ventilated titanium pistons for optimal performance. At the rear, AP Racing four-pot calipers bite down on two-piece rotors, which are the same diameter as the front (ø355mm). Performance friction pads are used at each corner. While the car was at Cusco, Tomei were already underway on the engine build, which is when we dropped over to take a look at the bench dynamometer test.