The basic structure is from the 1st catalyzer from exit of turbo to the 2nd catalyzer of Center Pipe. The catalyzer has the most resistant part of exhaust system. Therefore by reducing the resistance here makes turbocharger perform better in boost and performance. R35 has twin turbo V6 engine and 2 catalyzers set for the turbo exit, so total of 4 catalyzers are mounted. But HKS has developed special Metal Catalyzer for R35. This catalyzer has high performance of purification and at the same time it has low pressure for only 2 of catalyzers. We employed lost wax method to make inside flow better because the turbo exit extension part has a very big influence. This will let VR38DETT power do its work. For Japanese Automobile inspection, we got exhaust test result certificate and passed exhaust gas regulation.