In the world of cars, there is a saying that bigger is better. However, does this also apply to exhaust systems on our vehicles? As many of us know, as automakers use lighter materials to construct more fuel efficient vehicles they tend to compensate for weight loss with larger engine and exhaust – sized components. This can lead to increased sound, but at what cost? With the number of aftermarket performance parts available today, one might want a louder sounding car even if it’s not faster.
Relationship between exhaust pipe size and sound
Let’s explore the relationship between exhaust pipe size and sound first. The decibel scale is logarithmic meaning every time you double the number, it increases by ten times. So if an exhaust system starts out at 96dB, for example, it will increase to 106dB with a 2.5-inch diameter pipe. Then if that was increased to 3 inches in diameter, it would be 116dB.
As you can see, this means that simply changing the diameter of one’s exhaust pipe results in more noise however these numbers are not typically found on actual mufflers but rather extrapolated from dB tools used during testing which are then applied to standard automotive muffler systems. This doesn’t consider factors such as cabin gain or other type of silencers that may be employed so you can see why these numbers are often higher than what a regular consumer would expect to find in their own car.
Also, the decibel scale doesn’t take into account a human’s ability to hear certain frequencies better than others. While a dog can hear well into the ultrasonic range at 20 kilohertz, humans have a much smaller window for hearing sound that is comparatively lower at about 2 kilohertz.
So what does this mean for your car? In reality, changing out your exhaust system from factory size to something larger will result in more noise but not necessarily twice the amount. This also means that you might be willing to pay extra money for bigger piping simply because it sounds cool even if it’s not really doing anything for performance gains.
So what actually generates exhaust sound?
Simply put, the sound you hear is caused by resonance. It’s similar to blowing air across an opened bottle or tuning fork; it creates a pitch at certain frequencies. Resonance can be amplified because of your car’s particular configuration whether that means the length and diameter of your particular piping system or the fact that cars are often built with muffler silencers specifically designed to minimize this effect.
Car manufacturers will design their exhaust systems to avoid creating too much resonance for precisely this reason. If they didn’t, there would likely be harmonics all throughout the powerband instead of just when you’re on throttle which could wear down engine components immediately — not good! So while it might seem like bigger is better in the case of your car’s exhaust system, in reality it isn’t quite that simple.
What Does Bigger Exhaust Pipe Do Exactly?
In short, bigger exhaust pipe means increased airflow and therefore increased horsepower. If you have a stock car with its original muffler and piping system, chances are your engine is restricted in some way by the factory configuration even if you don’t realize it right away.
How can I tell how big my exhaust is?
There are a few ways you can go about finding the diameter of your exhaust system. The first is to remove it completely, measure its outside diameter with a metric ruler and then take that number in millimeters. Another option would be to simply look at your muffler’s specifications online or find them on a sticker somewhere inside the car. Some cars will actually display this information right on the muffler itself.
If you still can’t find this information or simply want to test things out for yourself, I would recommend making use of a decibel meter app so you can get an accurate measurement of how loud your car actually is compared to others at various speeds and throttle positions. The dB scale isn’t necessarily linear so you should be able to gather at least some information from your measurements which could help you determine if bigger is better.
What’s the Best Exhaust System?
The best exhaust system really depends on what you’re looking for. While there are certainly downsides to larger piping, it should be noted that smaller diameter piping will restrict airflow and therefore horsepower. If you’re looking for something that’s relatively close to the factory size, I would recommend going down one step at a time (i.e. – if you have 2″ piping, go with 1 7/8″). This will help keep your car sounding like it should while making it run more efficiently.
If you want an exhaust system that’s bigger than factory but not too big like true race car muffler, I would recommend the MagnaFlow performance series . It has a reputation for producing noise similar to what you’d expect from larger diameter piping without actually being that much louder.
Of course if you’re looking for something on the racier side, there are plenty of other options out there as well. The problem is that you’re likely going to sacrifice a lot of the efficiency and fuel economy your car had when it was new which could quickly offset any gains you might make in horsepower or torque unless you make some other modifications at the same time (i.e. – increasing rev limit, increasing boost, etc).
Best Ways For A Louder Exhaust System
If you want to make your car louder without actually increasing the size of its exhaust system, there are a few things you can do. One option is to simply drive with the windows down which will increase air flow allowing for more noise. Another option would be to install an aftermarket muffler silencer. If done properly, this should help with noise levels while allowing your engine to pull in as much air as possible.
1) Performance Muffler
Tip Putting a muffler tip to your performance exhaust system will give it that race car sound while aiding in noise control. It’s not going to make up for noise-level deficiencies caused by other factors, but it can help you get closer to the maximum output of your current system.
2) Exhaust Resonator
Tip Similar to a muffler silencer, an exhaust resonator will help reduce noise levels but may also have a tendency to restrict airflow. As with any other aftermarket modification you make to your car, it’s best to do some research on the product first before making a purchase.
3) Crankcase Ventilation Hose Removal
Tip Removing the crank-case ventilation hose from your car’s engine can improve horsepower and torque by increasing air flow. If this is something you’re interested in doing, however, be sure to check for any relevant service bulletins or recalls as it could cause engine oil leaks .
Overall, there are plenty of things you can do if you want more power but don’t want to spend a ton of money. Making too many changes at once can be risky so it’s best to take your time and research each modification before making a purchase. The good news is that this process should start with your car’s exhaust system which is relatively inexpensive and fairly easy to upgrade from factory specifications. If you do decide to change the size or style of your piping, I would recommend going down one step at a time in order to avoid becoming overwhelmed while ensuring that your new muffler produces the sound and flow you’re looking for while remaining safe for highway use.