In this definition, RH means Race Header, an exhaust manifold and is illegal to use on US Public Highways and Roads because of the elimination of a Catalytic Converter, which causes green house gas emissions to enter the atmosphere and cause Global Warming. ..But who cares? :)
1. An acronym Toronto rapper YungJMP made which stands for real humble soldier. He got the name from Daboii and his song Humbe which influenced him to make RHS.