The Top Secret Silvia is a heavily modified S15 Silvia that competed in the Japanese D1 Grand Prix drifting series. It was prominently driven in the 2004 D1 Grand Prix season by Ryuji Miki, whom became the championship winner of the 2004 season.
The Top Secret Silvia was designed to offer strong drifting capabilities, which were achieved by combining a stripped out base with a near 50/50 weight balance with an extensively upgraded turbocharged engine that produces 534 hp and 380 lb/ft of torque.
The engine was built using an SR20 cylinder block with an HKS supplied enlargement kit and Tomei camshaft, along with an HKS turbocharger and a custom exhaust manifold. The fuel system was upgraded with 1000cc injectors and a second fuel supply line with an additional fuel pump. The cooling system was also overhauled to enable a V-mount intercooler setup.