Im doing some exhaust shopping for my fit. Specifically the js racing set up but have i have a question. One versions lists ems and one doesnt. Is there a difference between non ems exhaust and ems exhaust? Im getting the full set up header, delete pipe, main pipe and muffler. Other mods are a hondata flash tuner, bisimoto valves, springs, and cam shaft. K1 rods.rz crew 75 mm pistons. R18 throttle body and weapon r intake manifold. The head was also ported and polished.