The phrase "pipe exhaust" refers to the gases or fumes that are released from a vehicle's exhaust pipe after the combustion process in the engine. Full definition
The rear apron can be mounted together with the original exhaust pipes or together with optional available 4 - pipe exhaust tips. (topspeed.com)
The twin pipe exhaust system, with two polished exhaust covers, is integrated into the rear bumper, which features an elegantly curved wing. (thetorquereport.com)