There is no mention or reference to cell density or converter volume dimension. The GESI catalytic converter will generate emissions that can meet or exceed the standards set via the EPA, not CARB. Almost every other use, together with leisure off-street use, could violate regional, state, and Federal guidelines. R44 https://bmwm4g82downpipe94319.bloguerosa.com/26323514/the-smart-trick-of-bmw-m3-g80-downpipes-that-nobody-is-discussing