The Japanese market X83 optioned 3.6 Turbo S had the earlier 930-style flat-nose louvered front fenders with flush-mounted, lift-up covered headlights, and various steel and fiberglass body components. Customers could choose between two different rear wing spoilers – the standard 3.6 Turbo style wing with the upturned rubber surround or the much larger spoiler which was featured on the 3.8 RS. The air inlets with horizontal grilles in the rear panels for additional engine cooling are reminiscent of the 930 Turbo S models, and are slightly asymmetrical- with the passenger side being slightly narrower to accommodate the oil tanks behind the quarter panel.
Six of the ten examples produced received the 964 Turbo spoiler, while the other four were constructed with the 3.8 RS spoiler. All ten were constructed in left-hand drive configurations and painted Polar Silver Metallic (A8) with black anodized exterior trim and a black leather interior (VD) with racing bucket seats.
All were equipped with the “Works Increased Horsepower” X88 engine option which was based on the 3.6 Turbo B2 engine built by Andial for the IMSA Bridgestone Supercar Championship. It incorporated a larger, single K27 turbocharger, an upgraded intercooler, modified cylinder heads with larger ports, higher output fuel injectors, and more aggressive camshafts. The M64/50 X88 were stamped with a unique “S” on the engine case that is about twice the size of the engine numbers. The X88 equipped engines delivered 385 horsepower at 5,750 rpm, approximately 25 more horsepower than that of the standard 3.6 Turbo. Torque rose to 384 pound-feet at 5,000 rpms. All were equipped with a stronger flywheel and clutch package to handle the extra power and torque. The G50 five-speed manual transaxle was equipped with a ZF limited-slip differential with 20 percent lockup under acceleration and 100 percent under deceleration.
These cars were all fitted with standard 3.6 Turbo suspension, including 21 millimeter anti- roll bars at the front and 22-millimeter at the rear, and Boge shocks and struts. The ride height was lowered by about an inch and a half to enhance handling at the suggestion of racer/engineer Roland Kussmaul.
All of the X83 examples were sent directly to Porsche’s Japanese distributor of that period, MIZWA Limited in Tokyo, which added special Japanese-language safety and emissions-equipment labeling on the interior’s left-side armrest and in the engine compartment.