Dynamic exhaust system; Two-mode exhaust; 2021 Cadillac CT5-V features dual-mode exhaust. RPO Identification. A dual-mode exhaust system has traditionally carried the GM RPO code NPP.

Planning exhaust-system mods? ... exactly 100 out of 100 hot-rodders will not be able to correctly identify the function of an exhaust resonator. Notwithstanding, ...

Flowmaster's American Thunder 2 1/2-inch exhaust system is constructed from 16-gauge aluminized steel tubing and includes everything you see here to give you a complete header-back installation.

Chris Werner, attorney at law, gives the facts on what exhaust systems and nitrous systems are legal in what state and what you could do to avoid a ticket, only at GM High-Tech Performance Magazine.

It is a requirement for cars to be equipped with a catalytic converter, or “cat”, which is part of the car’s exhaust system. Removing the cat is therefore illegal.