Advice on what to consider when selecting your performance exhaust
The best decisions are informed decisions, and AutoAnything is here to arm you with all the tips, hints and expert advice you'll need to choose the right performance exhaust system for your vehicle. We've done all the leg work of researching and analyzing the oceans of exhaust information for you, and have broken it down into these easy-to-digest categories:
All of the performance exhaust systems that AutoAnything carries are crafted from steel because of its unrivaled resistance to rust, corrosion and deterioration. However, there are varying grades of steel that offer different degrees of durability. Since you have more important things to do with your time than research metallurgical properties, we've mined all the data, hammered out the important facts and eliminated the unimportant slag.
- Aluminized Steel (Good)
- For the same brilliant look of aluminum without the extra costs and maintenance, aluminized steel is the way to go. Heavy-duty steel piping is hot-dipped in a special blend of aluminum-silicon alloy, which infuses the original steel with optimum corrosion resistance. For an aluminized steel system, turn to Flowmaster, Magnaflow or Edelbrock.
- 409-L Stainless Steel (Better)
- As the cost-effective alternative to 304 stainless, 409-L is a low carbon steel with greater strength, durability and corrosion resistance than the vast majority of stock exhaust systems. Go with Bully Dog or Gibson for a durable 409-L exhaust system.
- 304 Stainless Steel (Best)
- Infused with the highest concentration of chromium and nickel, 304 stainless steel delivers by far the ultimate in corrosion resistance, rust resistance and durability. When you want the best metal on the street, turn to Corsa, Borla, Dynatech and Volant.
Size does matter when you're deciding which performance exhaust system is right for your vehicle. If the pipe is too narrow, it creates a lot of restriction that robs you of horsepower, torque and fuel economy. On the other hand, piping that is too large for you motor will hamper engine scavenging, which will also slow you down. Follow these handy charts to decide which pipe diameter is right for your vehicle.
| Diesel Engines |
| Stock Horsepower Rating |
Pipe Size |
| Up to 450hp |
4" diameter |
| Up to 550hp |
5" diameter |
| Above 550hp |
6" diameter |
Sure, releasing 20 or 30 extra horses from your engine is a big gain, but 40 or 60 bucking stallions of power is twice as nice. When a performance exhaust system joins forces with performance exhaust headers, the resulting reaction under your hood is a potent marriage of brute strength and outstanding efficiency. How does that affect you? A double dose of horsepower, torque and fuel economy gains. Add to that the even meaner guttural growl that'll be rolling out from your vehicle, and it just makes sense to replace your clunky factory-installed exhaust manifold with high-performance headers.
Auto manufacturers cut corners where they can, and exhaust manifolds are a glaring example of design neglect. This disregard is unfortunate because the exhaust manifold is the all-important first step in the journey your exhaust makes from the cylinders out into the atmosphere. When you replace your restrictive manifold with racecar-inspired headers, your vehicle will breathe easier, scavenge exhaust better, and run at cooler temperatures. Not to mention that your engine compartment will look like the inside of a million-dollar NASCAR.
While exhaust headers are wrought from the same basic types of steel (304 and 409-L) as cat back exhaust systems, they also have special finishes to withstand the extreme temperatures created by the engine. There are a number of different coatings ranging from the mild to the wild.
- Nickel-Chrome Plated (Good)
- Mild-duty steel tubing with nickel-chrome plating for extended durability and longer life. The bright shine will naturally discolor after regular usage. Check out the chrome exhaust headers from JBA Headers, Doug Thorley Headers or Bassani.
- 409 Stainless Steel (Better)
- Heavy-duty stainless steel tubing that's left uncoated, yet is highly durable and resistant to corrosion. Like the Nickel-Chrome Plated finish, 409 stainless steel will eventually discolor from normal usage. To get your hands on stainless steel headers, check out Dynatech, JBA Headers, DC Sport, Gibson Headers or Borla.
- Ceramic Coating (Best)
- Silver ceramic coating gives excellent thermal protection and corrosion resistance. It reduces under-the-hood temperatures and has a bright, long-lasting shine. Though professional-grade, ceramic coatings are used by most exhaust headers companies, including JBA Headers, Pacesetter, Doug Thorley Headers, DC Sport, Gibson Headers, Bassani and Edelbrock.
The biggest misconception about performance exhaust systems may be that they are extremely difficult to install, but nothing could be farther from the truth. You don't need a degree in welding to bolt these systems onto your rig. In fact, you don't even need a soldering gun.
Your performance exhaust will arrive in multiple sections that, once fitted together, form your complete system. The pipes are slightly tapered at the end, which allows you to just slide the different pieces together. To prevent any exhaust from leaking out of these joints, your kit will include easy-to-use pipe clamps that fuse the sections. After you finish assembling the exhaust system, all you have to do is swap out the old pipes with the new ones. In most cars, trucks and SUVs, the factory-installed pipes will have to be cut away from the catalytic converter using a reciprocating saw or hacksaw. Once the old pipes are off and in the garbage, your new performance tubes are ready to move in. Luckily, our performance exhaust systems use factory-style hanging hardware, so you won't have to modify your undercarriage to install your new pipes.
If an engine ran perfectly, the only byproducts floating around in its exhaust would be a bit of nitrogen, some carbon dioxide and water vapor. While combustion has been greatly improved since the days of the Ford Model-T, it has not yet reached that level of complete efficiency. As such, those puffs of fumes that shoot out of our tailpipes contain a noxious slurry of harmful elements, including carbon monoxide, hydrogen, unburned fuel, hydrocarbons, and traces of aldehydes, alcohols, ketones, phenols, acids, nitrogen oxides and carbon. Since these elements have the potential to wreak serious, irreparable havoc on the planet's atmosphere, your factory-installed exhaust system is designed to filter out as many pollutants as possible.
Because auto emissions affect us all, there are laws on the books that dictate just how much vaporized waste can roll out of your tailpipe. In order to ensure that cars, trucks, SUVs and vans are in compliance with these laws, they have to pass a smog test every couple of years. However, there is no single federal standard for acceptable emissions levels. Thanks to the Tenth Amendment of the constitution, each state in the USA has the authority to determine its own acceptable auto emission levels. What's good in Wyoming may not fly in Delaware.
While there is no single smog canon, there is a sure fire test for performance exhaust manufacturers to know if their systems will be legal throughout the Union—does it pass in California? California is known for its rigid smog requirements. The California Air Resources Board (CARB) is a governor-appointed panel of scientists, lawyers and business men and women that sets the bar for emissions levels. California has the most ambitious emissions controls in the nation. Therefore, if an exhaust system can pass in California, it can pass anywhere else. When an exhaust system, or any performance part, claims to be "50 state street legal," it means that the product has been tuned and tested to meet California's strict smog requirements.
Some performance exhaust systems are designed for "off-road" use. This means that these particular systems are not designed to pass smog testing, and are not legal for street use. There are exceptions to the rules, though. In California, for example, any vehicle that is 30 make-years old or older is exempt from smog certification. Check with your state's Department of Motor Vehicles (or its equivalent agency) for the laws of your land. When equipping an off-road auto, pick up an exhaust system by BD Diesel, Heartthrob, MBRP, Dynatech or Bully Dog.
We hope you have found our Exhaust Systems Research Guide Center a good guide in helping you choose the best Exhaust Systems for your vehicle. It is AutoAnything's goal to provide the most information on the Internet and through our Auto Accessory Specialists on every product we sell. If you have any information that you think could help improve this section, please email us at researchcenter@autoanything.com.