What does dual exhaust do?
A dual exhaust system distributes a vehicle’s engine exhaust between two separate exit routes, usually ending in two separate mufflers. A single exhaust system sends all exhaust gasses through one exhaust path and muffler. If your engine has multiple cylinder banks (typical with six or more cylinders) and you have single exhaust, a “Y” pipe connects both cylinder manifolds to a shared exhaust pipe. From there, exhaust passes through one oxygen sensor, catalytic converter, and muffler. In a dual exhaust system, two exhaust pipes (usually connected to each other in an “X” or “H” pipe configuration) distribute the exhaust between two different sensors: the catalytic converter and muffler arrays. (Single mufflers with two intakes are also available.) With dual exhaust, your engine expels exhaust gas faster (using less energy) than with single exhaust. Most small-engine, non-turbo passenger vehicles come with single exhaust. Dual exhaust comes on certain vehicles featuring engines with six or more cylinders.
Either single or dual exhaust may be better, depending on the vehicle and whether you’re interested in the performance benefits and classic muscle car engine sound that dual exhaust can deliver.
Dual exhaust is better for:
- Engine sounds: The “hot rod” sounds of dual exhaust are a matter of taste (and hotly debated among car enthusiasts). Depending on exhaust pipe configuration, dual exhaust can deliver a deep, throaty sound or a higher-pitched, exotic-car sound.
- Performance and fuel efficiency: The performance and fuel efficiency benefits of dual exhaust come from opening more pipe space for exhaust to pass through (lowering the backpressure), and doubling the vehicle’s oxygen sensor, catalytic converter, and muffler capacity. The faster an engine can “exhale,” the faster it can “inhale” fresh fuel. And the less energy your engine devotes to exhaling, the more energy it can devote to its main job of moving your vehicle.
Single exhaust is better for:
- Lower service costs: With just one exhaust pipe, oxygen sensor, catalytic converter, and muffler to maintain, single exhaust has a lower cost of ownership than dual exhaust.
- Vehicles that wouldn’t see performance benefits from dual exhaust: The performance gains of dual exhaust will only be noticeable in high performance or large-capacity engines. That’s why single exhaust comes standard on most vehicles with non-turbo, four-cylinder engines.
- George Rumore of the muffler manufacturer Stainless Works was quoted in an April 25, 2015 article on SuperChevy.com Read the article.↩
