These mufflers and resonators have been developed by a continuous r&d effort. They have a quieter, deep sound. The muffler housings are constructed from mild steel tube and spun ends. They are fully externally tig welded for maximum strength. The internal perforated tubes are 409 stainless steel. An additional feature is an expansion joint in the perforated tube to allow it to expand and contract without causing fatigue and eventual failure in a very hot rotary exhaust environment. The perforated tube is wrapped in a thick layer of INOX( stainless steel wool) . This provides a heat barrier between the perforated tube and the packing. The packing is either high temp. rockwool ( 750 deg C) or high quality stranded fibreglass (700 deg C) when INOX is wrapped around the perforated tube. I prefer fibreglass in most circumstances because it appears to be more tolerant to carbon deposit which tends to make mufflers noisier. Where sustained full throttle application occurs I prefer rockwool which has a higher temp capability. It is important to tune the engine correctly and not run too rich which produces the carbon deposits in the muffler. These mufflers and resonators due to the expansion joint, with some effort , can be repacked if required giving it a second life. The resonators are fully packed with INOX in most circumstances.These mufflers and resonators are also suitable to fit to most high performance vehicles. For example Mitsubishi Evo, Nissan GTR, and Subaru WRX where less noise and high flow is required. Custom sizes are available on request.
If mufflers or resonators are subject to excessively rich air/fuel mixtures they will become carboned up and the end result will be that they will be noisier but the flow capacity will not be affected.