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Everything You Need to Know About Catback Exhausts in Los Angeles

There are many valid reasons why someone may want a cat-back exhaust system. These include enhanced fuel efficiency and engine performance because the engine doesn’t have to try as hard to get the exhaust out of the exhaust system, increased exhaust noise, or simply for aesthetic purposes.

Catback exhaust systems include everything from your catalytic converter to the end of your tailpipe. This includes the pipe between the catalytic converter and the muffler, the muffler itself, and the length of pipe that emits the exhaust into the open air.

 When this area of your exhaust system is replaced, it is usually replaced with pipes that have a larger diameter than the original pipes (between the catalytic converter and muffler, and tailpipe), and have a glasspack muffler. Glasspack mufflers allow the exhaust to go directly through the center of the muffler.

Doing this limits back pressure which is a good thing, but it doesn’t muffle very much sound. If this is what you want for your vehicle and you’re in California it can be difficult to determine if it’s even legal, let alone where to get it and what price you should expect, and that’s what we’re here for!

Are They Legal?

Catback exhaust systems are completely legal in the State of California because the modification starts after the catalytic converter and does not affect any of the emissions control components of your vehicle. If the Catback exhaust system you are looking at is expected to cause loud or unusual noise, that’s another thing.

The decibel limit in California regarding exhaust systems is 95 decibels. This gives you considerable leeway when you consider the fact that even high-performance muscle cars hardly ever exceed exhaust noise over 75 decibels. You should not have to worry about how to pass the emissions test with a modified car in California as long as the cat-back does not affect anything related to emissions control such as oxygen sensors.

The best thing you can do to be completely sure that you are in compliance with California’s Environmental Protection Agency and the California Air Resource Board (also known as CARB) is to look up the executive order number (also known as the EO number. The only parts that will have an EO number are parts that are acceptable under CARB and California’s Environmental Protection Agency’s regulations. If you are wondering about what the new driving laws are in California for 2021 are and if they make an impact on if you should get a cat-back exhaust system, the answer is no. There are no changes relevant to this situation.

What Are The Average Costs Involved?

So now that we know that cat-back exhaust systems are not among the 10 illegal car modifications in Los Angeles, you are probably now wondering about what costs are generally involved. Most worthwhile cat-back exhaust systems that are also street legal cost a fair amount. On average, you can expect to pay around $1,000, often before labor costs are included.

For example, if you have a 2015 – 2017 GT Mustang, you may have noticed how unexpectedly quiet your Mustang is compared to other powerful performance cars and want a “beefer” noise to accompany your vehicle’s presence. If this is the case, the Ford Performance Stainless Steel Touring 2 ½ Inch Cat-Back Exhaust System by Borla may be the perfect option for you.

This cat-back exhaust system will run you $1,379.99 if purchased from CJ Pony Parts. On the other hand, if you purchase a MagnaFlow Street Series Cat-Back Performance Exhaust System directly from MagnaFlow, you can expect to pay around $850 excluding labor. This cat-back exhaust system is suitable for Ford F-150s and is actually fairly simple to install yourself which can save you some money! It’s also worth looking into payment plans. Many manufacturers offer one that can make a cat-back exhaust system an option for you, even if you can’t buy one outright.

Where Can You Find Them?

One of the common car customization myths that people still believe is that you have to get your parts from the place you intend to have the part installed. This is not always true. Oftentimes, you can save money and time, as well as help ensure that the part you are purchasing is legal in your area, by purchasing from an after-market auto part retailer.

Not only can you get in trouble for violating California’s Air Resource Board and their Environmental Protection Agency’s regulations, the places that sell auto parts can also get in trouble for selling such parts.

Big aftermarket retailers are not willing to take that risk and will extensively research which products are okay for their shelves in each location to ensure they do not get hit with any penalties. For this reason, getting a cat-back exhaust system from a store like NAPA Auto Parts LA Truck & Auto, AutoZone, Pep Boys, or even Walmart is a good idea.

Of course, you can get the opinion of your local muffler shop to guide your decision. In fact, you can have them install the cat-back exhaust system that you purchased at another location if you are not comfortable installing it yourself or you simply just don’t want to be bothered by it.

Another thing you may want to consider is checking the manufacturer’s website after you find a catalytic converter at a big box retailer. After you know it’s acceptable and have checked the EO number, you can see if it is cheaper to buy it directly from the source. Not only that, they may even ship it straight to the shop you’d like to have it installed at for you.

Wrapping Up

Catback exhaust systems are great mods for many people and their vehicles. Because they do not affect the emissions system, they are completely legal in California so long as they aren’t too noisy. You can expect to pay around $1000, plus any labor costs imposed by the installing shop. Since big-box retailers also do not want to be penalized for violating emission regulations and laws, it’s a good place to start your search. Finally, check the manufacturer’s website in case you can get it at a more reasonable price. 


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