Pull up to any red light in America, and you will eventually find yourself sitting next to some hooplehead high school hipster who thinks revving his Honda engine is going to get him laid faster than Larry Flynt in a hen house. Looking all the world like a Justin Bieber back-up dancer who is down on his luck, he serenades you with the shrill, weed-eater sounds of his grapefruit-shooter-sized Coke can of a muffler. And as your brain slowly turns to jelly you think to yourself, “Who in the hell would ever want to put a performance exhaust on their car?”
Most car guys will admit it: The majority of the aftermarket exhausts you encounter while driving are cheap knock-off crap, and do very little for the car outside of making it annoying as hell. Stock (or OEM) exhausts on the other hand, have long been designed to be a way for automakers to cover their rumps, as they are typically quiet, unassuming, well-built, and 50-state legal. They also carry with them a healthy amount of ground clearance, are made of materials that prevent them from rusting-out too rapidly, and sport exhaust tips that seem tailor-made to the rear bumper of the car because they have been.
But while stock exhausts do indeed get the job quietly done, they cause that engine of yours to work a lot harder than it should most of the time. Mufflers aren’t just to blame either; everything from the engine back can contribute to poor fuel economy, crappy throttle response, and all manner of headache down the line. The majority of cars on the road have restrictive exhausts that feature piping diameters that are too small, with bends that are too sharp, resulting in a car that tries to exhale through the equivalent of an undersized Krazy Straw.
While a lot can be said for the gains one sees when they install a high quality aftermarket exhaust, know that they are not for everyone, or are not good for every vehicle. Some high-performance sport versions already have well-made, free-flowing exhaust system outfitted on them, so spending a few thousand dollars on something that will only offer modest gains may not be advisable for certain models.
Before we start reviewing what options are best for a car and why, let’s first cover some of the science behind an exhaust, because it’s a bit more complex than just some piping and a muffler or two. As hot exhaust gets pushed out of the engine, it gets fed into a header on naturally aspirated engines or into a downpipe on turbocharged motors. From there, it passes over oxygen sensors and snakes its way through a catalytic converter (or cat, for short), which acts as a filter for contaminants and keeps that car of yours legal when it comes time for smog inspections in states like California.
After the cat, it will likely hit a resonator or two, which adjust exhaust tone, and from there it will encounter a muffler, which true to its name keeps a car quiet-sounding. Save for the tip that follows the muffler, the fumes have now hit every single inch of the exhaust system, and are being released into the atmosphere. But these fumes could have escaped a lot quicker, and the faster and more efficiently an engine can expel exhaust, the less strain the motor will incur, resulting in more power and a boost in fuel efficiency.
If you own your own car, and it is time for a new exhaust system, or fancy a bump in power and efficiency and don’t mind a sportier sounding vehicle, then maybe a premium exhaust is right for you. Magnaflow is always a great place to start since being one of the biggest exhaust manufacturers in the car game gives them the ability to make whatever they want for whomever they want. From bolt-on cat-back exhausts, to all-out, header-back race exhaust, these guys do it all. They also sell universal pieces and kits, so if you know of a good welder who can tailor-make one for your vehicle then it might be cheaper to go that route.
If you are an import car guy, going with something from Cobb Tuning, ATLP, J’s Racing, APR, or HKS is always a safe bet. All five of these companies offer outstanding craftsmanship and use only the best materials. There are also a number of trustworthy manufacturers that specialize in focusing on big American V8 engines, like Borla, and the king of all truck exhaust makers, Flowmaster. Naturally, various engines and exhausts have different notes, finishes, materials, tips, installation styles, and warranties, so be sure to research your car thoroughly before committing to something that costs this much.
Be on guard if a mechanic tells you that your catalytic converter is shot, and that you need a whole new exhaust: A bad cat does not typically cause the rest of the system to malfunction. Sure, if it is rusted out and they can prove this, then it is time for a new one. But 90% of the time, a bad cat can be replaced for far less than you might expect, because while the dealer is asking for a few hundred bucks for one, Magnaflow is offering universal cats for as low as $70 at most auto parts stores. Just check out Magnaflow’s converter recommendation page first to make sure you are getting the right one, and while you will have to pay for someone to professionally weld it in, that is going to be a hell of a lot cheaper than buying an OEM cat from the dealer.
As your anemic exhaust nears retirement, start doing some research on who makes what for your car. Think about replacing everything from the engine back, instead of from just the cat-back. Check dealer prices to see if a new stock exhaust is a cheaper route to follow, because if you plan on selling that car, an aftermarket system can be a huge turn-off for certain buyers. And remember that most high-end aftermarket exhaust systems are designed to outlive a stock unit, so in the long run this could be a big money saver for you.
More from Autos Cheat Sheet:
- How the Steel Industry Wants to Make Fuel
- The 10 Best Dog-Friendly Vehicles
- How to Get 81 MPG and See 48 States for $300