Switzer Performance Innovations (SPI) in Oberlin, Ohio, is different from most aftermarket firms because it is not just a tuner but an intricate research and development lab for high-end performance products. I was invited to the Nelson Ledges Raceway in Ohio to test-drive SPI’s latest projects: the Porsche 997 GT2 and Nissan GT-R. Initial laps were treated as a warm-up both for the machines and me, but my pace quickened as I began to rein in all 800 hp from these retuned sports cars. Soon I was passing gentlemen racers and embarrassing weekend warriors without any trouble. Predictable handling and braking characteristics in the corners, combined with eye-flattening acceleration out of the curves meant that objects in the rearview mirror simply stopped appearing altogether.
So how was this kind of power achieved? For the GT2, things start with the turbochargers on Porsche’s 3.6-liter 6-cylinder engine. Larger Garret GT30R-based turbochargers with custom billet compressor wheels on ball-bearing center sections in lightweight stainless turbine housings increase power output. These upgraded turbochargers compress massive amounts of air, which is channeled to the engine through Switzer’s own intercoolers. Inhalation duties—no small task—are tackled by custom-intake plenum with an oversized throttle body sparked by larger injectors and managed by a Switzer-tuned Engine Control Unit (ECU). A GT2-specific version of Switzer’s existing exhaust was also used because the stock Porsche system was just too restrictive and not designed to handle that much airflow.
As for the GT-R, Switzer wasn’t even going to bother with an upgrade package, but demand became too difficult to ignore. The first step was extensive data logging and analysis to optimize every aspect of Nissan’s 3.8-liter twin-turbocharged V-6 engine. After replacing the stock turbos with application-specific custom units and adding their NASCAR-inspired intercooler package, Switzer’s team of engineers cracked the ECU and altered the computer-governed limits.
While many aftermarket automotive tuners favor eye-catching body kits and ridiculously oversize rear wings, Switzer prefers to get recognition for the performance of its cars, not their appearance. The end result of their transformation creates vehicles with a vastly heightened performance prowess that appear bone stock to the untrained eye, which makes it all the more entertaining when you introduce the throttle to the firewall. (www.switzerperformanceinnovation.com)