I am designing an exhaust muffler for a so called wet diesel exhaust system. In the wet system seawater in injected in the gasflow. I need fiitings to connect rubber exhaust hose to the muffler. For seawater resistence I would like to use admirality brass or bronze. However according to the literature the content of sulfer in diesel exhaust gasses could affect copper allois. Would a stainless (316) casted fitting be a better material? The fitting contain a tube rotating in an other tube sealed with an O-ring. Is there a risk that gap-corrosion will occur in the gap between the two tubes (O.2 mm). Is there a difference in risk for gap-corrosion using stainless steel or a copper alloi?