What is CARB and why is it important to have a CARB EO# stamped on my performance headers?
CARB is an acronym for the California Air Resource Board, which is California’s regulatory agency tasked to set the state’s acceptable automotive emissions levels. Most performance exhaust systems are built to meet CARB’s strict requirements. Headers usually have a CARB EO# stamped somewhere on them. They have these because when your vehicle undergoes a smog test, it must pass both a mechanical and a visual inspection. A set of performance headers bolted onto your engine block could be grounds for a failure of the visual inspection, unless you have a CARB EO# prominently displayed right on the headers. If your vehicle qualifies for off-road status, then it does not matter.
