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BoatExhaust.comPompano Beach, Florida, USAHigh Performance Marine Exhaust Systems. Steve Snider, Owner |

| Q). Why are after market exhaust systems better than stock cast iron manifolds and risers? A). Aftermarket aluminum exhaust manifolds are lighter. Also, aftermarket aluminum exhaust systems have large individual runners for maximum horsepower gains. Q). What kind of speed gains can I expect? A). Typically 2-4 mph with single engine boats and 3-5 mph with twin engine boats. Q). What is reversion? A). Reversion is the pulling back of water from the riser where water enters the exhaust. The water is pulled back into the exhaust part of the head and into the cylinders of the motor. Reversion occurs with the exhaust systems that utilize short stock type risers when a cam change has been made in the motor and duration of the cam exceeds 230 degrees. Stock motors do not have a problem with reversion. To eliminate reversion long stainless steel risers are utilized for systems with altered cams. These are jacketed and inject water into the exhaust at a point much farther from the motor thus eliminating reversion. Q). I have a race motor in my boat with a big cam and a blower but I want to keep my silent choice (captain's call) - can I? A). No, you need to eliminate the silent choice system and run long stainless steel risers or reversion will ruin your expensive motor. To quiet motors, we offer muffling devices that are utilized at the exhaust tips outside the transom of the boat. |
