After extensive  R&D, HKS' flagship exhaust system is now   available with the  ultimate performance, sound quality and appearance.  Superior spec R is the high end model of the HKS exhaust systems. The durable full titanium exhaust system is lightweight and  weighs 10kg (22 lbs.) lighter than the stock exhaust system. The large radius piping layout  optimizes exhaust gas pressure and temperature allowing peak performance and an aggressive exhaust tone.  Dual layer titanium tips reduce heat  while the functional slits inside the tips assist in noise reduction.