HKS SILENT HI POWER EXHAUST CELICA GT4 ST205 3SGTE HKS Silent Hi-Power.HKS mufflers offer high performance and sporty appearance with the added benefit of reduced noise levels making it the best choice for more mature enthusiasts. Silent Hi-Power mufflers are constructed entirely of SUS304 grade stainless steel for high luster, long lasting performance. For certain applications, HKS has introduced the “Silent Chamber” which removes a lot of the lower frequency noise that can often be heard into the cabin even when cruising. The silent chamber removes this uncomfortable noise but due to its closed end design. Only a minimal amount of exhaust gas flows into it, meaning that the disruption to exhaust gas flow through the entire system is minimized and there is no harm to performance. Inspired and designed from endurance and GT racing in Japan, HKS developed its Hi-Power Exhaust system for both turbocharged and naturally aspirated applications. HKS has incorporated this new race inspired offset muffler and piping design into many street applications, which offers a greater flow and higher-PRM power gains due to the less restrictive design. This is achieved by eliminating unnecessary bends for the straightest exhaust path. For turbocharged applications, the large and smooth exhaust flow allows greater exhaust velocity for better mid-range boost response and high-RPM power. Naturally aspirated vehicles also benefit from greater exhaust flow capacity as engine tuning levels increase.31019-AT010