If your vehicle comes with a resonator, then it will cancel out a specific range of sound frequencies when you go through the acceleration process. The sound waves have specific amplitudes which this device cancels out. Each vehicle comes with its own range that gets removed from the final process, usually choosing the sounds which are the least pleasant to hear.
Most resonators cancel out the harsh ranges and sounds where your exhaust notes would produce a loud droning sound, an irritating buzz, or a high pitch which could trigger headaches or other health issues.
Some resonators will make your exhaust sound aggressive and loud. A Ford Mustang uses a resonator/muffler combination tuned to make that “blub, blub, blub” sound. Next to no muffling. Plus, it’s a V8.
If you’re thinking about a resonator delete to change the exhaust composition of your vehicle, then these are the pros and cons to look at more closely.
List of the Pros of a Resonator Delete
1. It will change the sound profile of your exhaust.
Many vehicles experience a deeper, more authentic sound when equipped with a resonator delete package. Since the main function of this device is purely cosmetic, nothing happens to your vehicle when changing the noise profile. If you have a pretty big muffler attached to the vehicle too, then the changes could be minimal. You’ll just hear more of the frequencies which would normally be blocked by the device.
2. It will reduce the weight of your vehicle.
If you pull the resonator off your vehicle for good, then you’ll reduce the overall weight profile. A lighter vehicle will give you a slightly better fuel economy under most circumstances. The change is mostly for the sound. You might be able to achieve an extra mile per gallon under a best-case scenario.
When you’re looking for a true performance gain, then take off the muffler too. Replace it with a high-quality option like those produced by Carlsson or Brabus to generate results. Most owners find, however, that their current muffler already maximizes their results, with or without the resonator delete.
3. It will usually eliminate the drone once you reach speed.
One of the primary complaints about the exhaust profile once you use a resonator delete is that a drone-like sound comes from the vehicle as you accelerate. It can be a loud, annoying pitch on some vehicles, this is true. Once you reach your cruising speed, however, the sound typically vanishes. Expect the noise to be present when punching on the gas, then enjoy the quiet once you reach your speed.
That can be a disadvantage if you do a lot of city driving, like a daily commute to work. Most people do like the sound profile, so it is often worth the small investment.
4. It comes at a minimal cost.
Most vehicles can have a resonator delete completed for $100 or less, even at the shop. The only cost issue to consider is if you must cut out the device, then weld a new straight pipe to replace it. That can push the cost upwards of $300 in some regions. There aren’t many modifications that will alter your sound profile in a positive way like this one does, which is why it’s worth considering.
5. It is generally a legal modification on most vehicles.
You can quickly determine if a resonator delete is legal based on where its location is on your vehicle. Anything that happens in front of the catalytic converter is not permitted in the United States. If you mod something after the cat, then it is generally legal – assuming that it doesn’t change the emissions profile of the vehicle. You will still need to check with your local state or jurisdiction before completing this process.
Some states and cities do not allow any modification to a factory exhaust system.
6. It could experience a small horsepower gain, depending on your circumstances.
The resonator delete can sometimes improve your overall horsepower rating if there is heavy buildup within your vehicle’s exhaust system. Your goal is to create a little back pressure on the engine to create better efficiencies, but not create something that is close to a blockage.
If there is soot or other forms of building up within the device, then the resonator delete with a straight pipe will remove it, helping you to at least restore the engine to its original horsepower rating. Expect a maximum boost of about 5 horsepower for most vehicles in the best-case scenario.
7. It creates a clean appearance for the underbelly.
The exhaust system is necessary for maximum performance. Some drivers have an issue with the way their resonator combines with their muffler(s). It can sometimes look clunky and unsightly, which is not a situation you’d want if your plans include showing the car. By going through the resonator delete process, you can clean up the underbelly to help it look more appealing. The straight pipes tend to look a lot better than the device that some people mistake as their muffler.
8. It allows you to keep your current setup for the muffler.
If you decide to proceed with a resonator delete, then you get to keep the muffler profile. That even means you can stick with a dual exhaust if you want. Some models might need to have a Y pipe at the end to make things work, but the mod creates a minimal impact on the overall system. Then you’ll receive a sound that is deeper and throaty in return.
9. It can modernize the systems of older cars.
Most of the benefits that you’ll find associated with a resonator delete come from owners who updated an older vehicle using an archaic exhaust system. When you remove the resonator, high engine speeds will create strong performance gains after this modification. Old cars perform even better when there is a muffler delete that works with the resonator delete. Since the vehicle sounds more like a muscle car once you’re finished with this work, you receive a series of benefits that are difficult to ignore.
10. It doesn’t require additional maintenance once complete.
Once you’ve finished your resonator delete project, then you’re finished with your exhaust system. There’s no need to come back to it for inspections or repairs, especially if you’re working with an older vehicle. Although you might encounter some warning lights on newer models with this mod, it doesn’t typically impact the mechanical performance. If you do find performance issues after completing this project, it’s easy enough to restore the exhaust system back to its original condition too.
11. It comes available in several variants.
An excellent example of the variants available with a modern resonator delete kit comes from the S550 Mustang GT from 2015-2017. It’s a popular modification of this model because of the way the exhaust is set up. You just cut and clamp, which then dramatically changes the tone of the exhaust without being overly expensive. This option is available with the X-Pipe and H-Pipe variants. You can pair the resonator delete with almost any axle-back, stock mufflers, or anything OEM to have heads turn when you drive by.
List of the Cons of a Resonator Delete
1. It will cause more droning sounds to occur while you drive.
The primary benefit offered by the resonator is that it takes away the droning sounds which a vehicle creates when traveling long distances at high speeds. Once you hit the 3k to 4k RPM range, you’ll notice it begin to develop. As you increase your acceleration profile, the sound on some vehicles begins to resemble something more akin to a screech or high-pitched whistle. You might notice more of a rattle, vibrato, or tone that could be bothersome while driving too if you opt for the resonator delete.
2. It will cause you to lose some engine efficiency.
The exhaust resonator improves the overall performance of your engine. It creates a smoother driving experience when you’re at the wheel, allowing the engine to produce a maximum level of horsepower without using too much fuel to do so. Some vehicles experience a small drop in their fuel efficiency when the resonator delete kit is used because the engine is forced to work a little harder to create the results that you want. The impact is minor, but if your aim is for maximum impact, this disadvantage might come into play.
3. It can impact your power production
A resonator delete changes the way that the pulses generated by your vehicle move through the exhaust system. Think of this device as if it were a large echo chamber. It takes those pulses, optimizes their frequencies, and this makes it possible to achieve better power production. Taking this away makes the engine work harder too, so not only are you losing some of your fuel efficiency, there’s some power loss to contend with as well. It might look and act like a muffler, but it does much more than that too.
4. It makes you lose the signature sound of your vehicle.
Many vehicles, from a Ferrari to a Ford F150, have a distinctive sound that allows them to be recognized when you’re out on the road. If you incorporate a resonator delete package as a modification, then you’ll shift this profile. Although there aren’t emissions issues with which to contend like other mods, changing the tone could make it more of a challenge when you decide that it is time to sell the vehicle in the future.
5. It can reduce the speed of your exhaust flow.
Modern vehicles have part of the combustion cycle that involves pistons. They push the exhaust gas used by the engine out of the chamber before filling up with fresh air and fuel. The resonator exerts an additional force on this process, helping the gases move faster through the system. It uses the sound waves from the device to evacuate the combustion chamber, moving the exhaust through the pipes, then eventually out of the muffler. Stronger waves create a better vacuum. You’ll lose that if you choose a resonator delete.
6. It offers a minimal weight reduction in even extreme circumstances.
Let’s use the most extreme circumstance of a resonator delete for this example. Let’s say the device weighs about 100 pounds. With the average mod, you’re going to achieve an 80% weight loss from this one item only. That means you’re taking the system down to 20 pounds. According to the Environmental Protection Agency, taking 100 pounds out of a vehicle will increase your fuel economy by between 1% to 2%. That equates to about $0.05 per gallon for the average vehicle.
Now let’s say on a full tank of gas, you’re going to put in 15 gallons. That means your cost savings equates to about $0.75. You must reduce the weight profile of your vehicle by 10% to achieve a 4% mileage boost. You could get better results by running on a half-tank of fuel instead with some vehicles.
7. It could impact your warranty.
If your vehicle is still covered by a warranty, then making a change to the overall exhaust system could void it. Some repairs are costly (like a transmission replacement), so if your entire warranty is canceled because of a resonator delete, then the risk isn’t worth the raspy reward of a purer sound. You can avoid this disadvantage by using this option with an older vehicle. Then you’ll be the person who has the car or truck that everyone hears when you start it up to go somewhere. That can be a problem in some neighborhoods too.
8. It might trigger your check engine light.
Because the resonator delete is part of the back end of the exhaust system, removing the device can sometimes impact the performance of your catalytic converter. When that occurs, you can sometimes trigger a check engine light warning or a code in your system because there are backpressure changes that occur. Although you won’t fail the emissions test because you haven’t removed the cat, you might find it more of a challenge to find someone to service your vehicle for basic services.
This disadvantage is especially prevalent in the newer model cars out there. You’ll lose the flow advantages that were built into the vehicle too.
9. It could create some idling issues.
Most idling issues for a vehicle, especially an older one, are due to a catalytic converter under-performing. If there isn’t enough back pressure placed on the engine, then it may try to stall on you when your foot isn’t on the gas pedal. Although the risk of this disadvantage happening from a single resonator delete mod is quite low, it is still a possibility on a vehicle that hasn’t seen much in the way of exhaust service over the course of its lifetime.
10. It could impact the paint on your vehicle.
This disadvantage is based on where you decide to make your cut with the resonator delete, and if you decide to get rid of the muffler while you’re at it. When you run on a straight pipe, then the exhaust system produces a lot of debris and gunk that can foul your paint job. There are often issues with this stuff that can create a negative impact on the undercarriage of your vehicle.
These pros and cons of a resonator delete can help you decide if a modification to the sound profile of your vehicle is worthwhile. Some owners might see small efficiency gains, while others could experience losses. It all depends on the amount of backpressure your specific design creates for your user profile. If you’re looking for a cheap and easy mod that will allow your vehicle to meet your noise expectations, however, then there isn’t much to lose with this option.
Brandon Miller has a B.A. from the University of Texas at Austin. He is a seasoned writer who has written over one hundred articles, which have been read by over 500,000 people. If you have any comments or concerns about this blog post, then please contact the Green Garage team here.