Hey whatups HONDA-TECH, I'm thinking about getting an Thermal R&D exhaust that is 2.5" i know they have 3 different models which is the Turbo (3") the ST and the CL... but I can't find out how many inch" is the ST or the CL any of you guys have an idea or a clue? is it 2.5" or 2.38"

 

Most likely might be a 2.5" outer diameter pipe but only 2.38" inside. That little bit of difference shouldn't be that noticeable.