To fill the body of the case, Greddy uses some unique ceramic wool cones instead of simple batting. The geometric shape of the cones is essentially non-resonant which helps them damp out noise better than simple batting.
|The Greddy RS main pipe is much lighter, larger in diameter, made of superior materials and has much better flow than stock.|
The RS exhaust also has another small muffler that acts like a resonator upstream of the main muffler. This muffler also has a perforated core inner tube and stainless wool packing. As an option the RS also comes with a thing we call the butt plug that reduces the outlet diameter forcing more exhaust gas into the muffler packing. The butt plug really quiets the muffler down but it probably also reduces power. We didn’t bother running it for long and all of our power testing was done with it removed.
|The 80mm Greddy RS is much larger in diameter than stock and should support over 500 hp.|
The exhaust installation was a snap, we literally installed it at home in about 15 minutes. The fit of the exhaust was superb and there were no rattles or any other indications of contact between the exhaust and the body. Even with the butt plug removed, the Greddy RS exhaust was fairly quiet although it was definitely much louder than stock. The exhaust note reminded us of our Project Evo IX which has a Greddy Ti-C exhaust with a WORKS resonated downpipe.
|Chris reinstalls one of the stock rubber hangers on the RS main muffler.|
Naji Dahi of Looney Tuning once again made himself available for power testing and data logging and the exhaust produced. The Greddy RS made 294 whp @ 6633 rpm and 288 lb/ft of torque at 4297 rpm, an increase of 9hp and 5 ft lbs. The peak gains were 11 hp and 9 lb/ft of torque. The gains were pretty consistent over a wide rpm range for a lot of area under the curve. This is also 30 hp and 24 lb ft more than stock!
|The Greddy RS exhaust fits perfectly.|