Thinking about deleting the muffler in your car or truck?
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Vince from Scanneranswers here to talk about vehicle muffler delete system pros and cons.
The muffler is an integral part of the exhaust system. The main job of the muffler is to silence the noise created by an internal combustion engine. Without it, the vehicle will rev more loudly like a racing car.
But then again, isn’t that what some car lovers want? A muffler delete system (or simply the process of removing the muffler/mufflers) will make the vehicle sportier to drive courtesy of the louder exhaust sound. But is it true that a muffler delete system will also add horsepower? Will it give your car better acceleration?
In order to answer all the questions, it is better to discuss the pros and cons of a muffler delete system. Knowing the benefits and drawbacks will allow you to make a wise and informed choice.
I can understand why people are drawn to muffler delete systems. Vehicle mods are not exactly cheap. But by simply removing the mufflers, some people say they get more performance and a more thrilling sound, all by simply loosening a couple of bolts and hangers. If you have money to spend, you can buy a set of better mufflers that are less restrictive than the stock units. This will have the same effect as a DIY muffler delete system but without the added cost.
Understanding the Exhaust System
In a normal production car or truck, the exhaust system is composed of 6 parts:
- catalytic converter
- exhaust tip or tail pipe
The muffler in particular contains an inlet tube, a resonator chamber, and a set of tubes with perforations to reflect sound waves. The muffler is the final step in the exhaust system that manages to cancel out the noise created by the motor.
With that in mind, removing the muffler to create a muffler delete system will make the vehicle louder. How loud? It depends on the type of motor.
But one thing is for sure: removing the muffler is enough to wake up your neighbors in the morning as you start the vehicle.
In newer model cars, removing the stock muffler will result in a dire consequences and often cause the check engine light to come on. The carmaker spent a considerable amount of time and resources to perfectly design the ideal exhaust system for a particular vehicle. It is similar to messing up an otherwise perfect dish by adding less salt. An expertly-engineered exhaust system will provide better flow than a muffler delete system, hence giving better performance with the mufflers installed.
But in older cars with archaic exhaust systems, removing the muffler may result in noticeable performance gains at high engine speeds, not to mention a louder and more exhilarating exhaust sound. However, emissions and issues with road-legality will be a different matter altogether.
If you do decide to delete the muffler in your car, it’ll will probably make the CEL light come on. An OBD2 tool will be able to easily clear this warning.
Pros of Muffler Delete System
1. More horsepower at high engine RPMs.
This holds true for older cars or those that were built 15 to 20 years ago. Removing the muffler will significantly increase the exhaust flow while reducing harmful engine back-pressure. Old-style mufflers are many times more restrictive than the newer mufflers of today. It is easy to understand why a muffler delete system can prove beneficial to older cars or old race cars. It not only makes the vehicle sound more muscular, but the horsepower and torque gains at high speed are hard to ignore.
However, this is not true if we’re talking about a new or modern car. Like I said earlier, technology has gone a long way. Carmakers now have access to muffler systems that are designed to improve exhaust flow without creating a lot of noise. In most cases, a muffler delete system or a set of aftermarket mufflers (or axle-back mufflers) may do more harm than good and result in less horsepower. Removing the muffler will also force the ECU to go into LIMP mode, made evident by the check engine light on the console.
2. Better exhaust sound.
Since a muffler delete system will basically open the taps in the exhaust system, the rushing hot gasses will also produce a louder and more aggressive exhaust sound. Some people even find this addictive as the sound gets better the deeper you bury the pedal. Those popping backfiring noises are also ear candy for enthusiast drivers.
Cons of Muffler Delete System
1. Droning sound.
While the sound gets better as you accelerate, the muffler delete system will also give your vehicle a noticeable drone while cruising at normal speeds. The drone can get so bad that it will affect the NVH tuning of the interior, which will prove annoying on those long drives.
2. Poor idling and mediocre engine performance.
Cutting off or removing the muffler in a modern car will make the ECU and exhaust sensors go wild. The result? Less performance and poor idling.
3. Gunk or dirt buildup.
Depending on where you cut the muffler, the straight pipes will leave a ton of gunk and dirt. The worst part, the gunk may be strong enough to mess with the paint in your vehicle.
Instead of resorting to a muffler delete system, it is better to purchase a set of aftermarket axle-backs or cat-back exhaust kits from a reputable manufacturer like Borla, Flowmaster, or similar. Since the kits are specifically designed for a particular make and model of vehicle, aftermarket mufflers will reduce back-pressure and improve the flow without the drawbacks associated with removing the mufflers altogether.
With a high-quality aftermarket exhaust kit, your vehicle will sound better and produce more horsepower while making it look better in the process, especially if you choose a stainless steel muffler kit.
If your car is a daily driver, leave it alone and let the mufflers do their job. But if your vehicle is tuned for performance or intended for track days, a muffler delete is an easy and relatively cost-free way to improve the exhaust sound for better engine breathing. When combined with a carefully-designed aftermarket intake system, you can enhance the character and performance of the vehicle without spending thousands on expensive engine mods.
Oh, and if you have an old 5.9 Cummins or diesel like that, you gotta delete the muffler 😉
Vince G here with ScannerAnswers. Mike and Matt made me fill out this bio… I write on this site once-in-a-while when I’m not fishing or biking. I love fast cars and on weekends I sometimes work on them. I help with this site because I believe everyone should own and be able to use a wireless bluetooth OBD2 scan tool.