Hey guys. About 2 months ago I wrecked and crushed my header pipe on a railroad track. The dent is right AFTER the 180 degree bend coming out of the engine, it is pretty good sized, about half the diameter.... ouch! First off, how much will this effect the power output? Would the filling with water and freezing method work to push some of the dent out until I get a new one? The pipe is the factory steel I believe. Thanks for your help.