Exhaust gas a byproduct of combustion and it needs to be routed away from the cabin of the car. Without a proper exhaust system, exhaust gases would likely enter the cabin and the excessive monoxide can permanently damage your health or result in death. On top of that, the insane amount of exhaust noise would be very obnoxious. Therefore, it’s pretty important that you have a full exhaust system which routes exhaust gases away from the cabin of the vehicle.
If your car’s exhaust components are failing, you’ll likely see a decrease in fuel mileage and your car might not pass vehicle emissions tests. Components such as the catalytic converter are very important for decreasing emissions output and shouldn’t be removed for any vehicle which is used on the road.
Unfortunately, many OEM exhaust systems use very small diameter piping which results poor exhaust gas flow. With less exhaust gas flow, the piston has to work extra hard to push exhaust gases out of the cylinder which ultimately leads to reduced power output. The whole idea behind aftermarket exhaust systems is to eliminate exhaust gas restriction and improve power.
In case you didn’t know, heat is energy, and as exhaust gas cools, its velocity decreases. Harnessing this energy isn’t extremely important for a naturally aspirated vehicle, but it’s important for turbocharged vehicles. With hot, high-velocity exhaust gases entering the turbocharger, the turbine can be spun faster resulting in better spool times, more power, and ultimately much better thermal efficiency. You can harness even more of the energy by using an exhaust wrap which is designed to keep the heat inside the header instead of it dissipating to the air under your hood.
Your exhaust system is typically comprised of a few different components. For naturally aspirated vehicles, the exhaust system is comprised of a header, mid-pipe, and rear-pipe. For turbocharged vehicles, the exhaust system is typically comprised of a turbo header, downpipe, mid-pipe, and rear-pipe. Each application is different and some applications use different names for these exhaust components.
It’s important to note that all road-going application must abide by local and federal law with regards to emissions components such as the catalytic converter. These components can only be removed on dedicated track cars (where legal) and should never be removed if you use your vehicle for the street! Always check with state and federal laws before replacing your catalytic converter.
Typically, most enthusiasts install a catback exhaust system, which replaces everything from the catalytic converter back to the exhaust tip. Catback exhaust systems are typically the best bang-for-buck when upgrading your exhaust system and can also dramatically change how your car sounds.