Your classic exhaust system contains a resonator, catalytic converter, and muffler to lessen the emissions that a car produces. This combination of equipment will also lessen the sound levels experienced inside and outside of the vehicle. If you have a straight pipe exhaust equipped, then you have a pipe that starts from the header. It can provide you with more torque and horsepower with a racing engine, but it is usually only permitted on closed racing paths or circuits.
Unless there are jurisdictional exceptions, you cannot operate this setup on the road. These systems do not hold any boundaries with gas flow. It is just a straight pipe that goes into the air without a catalytic converter or a muffler.
You can draw some extra power from your engine when you use this approach. Your vehicle is going to be a lot noisier with this setup as well. Once you take a look at your local noise and emissions laws, you can take a look at these specific pros and cons to see if a straight pipe exhaust is the best approach to meet your needs.
List of the Pros of a Straight Pipe Exhaust
1. You will see an enhancement in your horsepower.
The primary advantage of equipping a straight pipe exhaust to a performance engine is that you’ll see a definite boost in your horsepower. This result occurs because the system reduces the amount of backpressure from the engine, allowing the exhaust gases to form with greater freedom. That means the engine can perform without the hindrances that are placed on it when using other systems. That means you’ll get a higher HP and your fuel economy will improve slightly at the same time.
2. Your vehicle will stand out from the crowd with a straight pipe exhaust.
When your vehicle has straight pipes, then people are going to notice. That’s why you’ll see many systems like this given a chrome finish to the exhaust tip. This design element makes the system look very appealing. You can even apply different welding methods at the tip to provide colored batters in red, blue, and green that make it even more aesthetically appealing. There’s the option to go with a twin pipe setup instead of a single pipe to give everything a sportier look.
3. You’ll hear the authentic sound of your engine.
A straight pipe exhaust might be louder than other setups, but it will also provide you with the true sound of your engine. Vehicles using this option sound raw and pure. This advantage can be quite appealing on the racetrack. If you equip it to the vehicle you drive to work each morning, then you might want to rethink your approach since the starting process will likely rattle some windows.
There are some small benefits that come in this category as well. You won’t need to change your muffler bearings any more since there won’t be one on your vehicle. Depending on what car you own, there is even the possibility of shooting flames out of the exhaust. People are going to hear you coming, so it is up to each of them to determine if they like the sound or not.
4. There are universal kits available to help you fit most vehicles.
You’ll find that there are custom exhaust tubing kits available today that can help you to equip a straight pipe exhaust to almost any vehicle. Before you decide on this option, you’ll want to make sure that your pipes are the correct diameter for your make and model. Nothing is worse than equipping a 2.5-inch circumference pipe to a car that wants to operate on a high-performance 4-inch design. You’ll also want to make sure that if you’re riding off-road that the design of your pipes is off-road compliant. You may need a model that is non-CARB compliant as well.
5. It will reduce the weight profile of your vehicle.
One of the primary reasons why racecars and track vehicles run with the straight pipe exhaust is that it removes the weight of the muffler and the catalytic converter from the vehicle. Saving a few pounds can be beneficial if you’re working to maximize the fuel economy of your car. If your vehicle runs a little heavy for some reason, switching to this setup can help you to reach your goals. Don’t forget to tune the car before taking it out at full speed to ensure your performance levels stay maximized.
List of the Cons of a Straight Pipe Exhaust
1. There is a lack of flexibility with this design.
You will need to tune your vehicle to the straight pipe exhaust design if you decide to alter its setup. There is not a lot of forgiveness in this approach either because even if your pipe size is a little small, you’ll lose a ton of power in your low-end torque. Depending on the design of your undercarriage, you might also need to do a lot of extra work to ensure there are minimal impacts on airflow and resistance while driving.
When you subtract or delete items from the current setup of most vehicles, then you create a lower power curve that actually robs you of performance. Your vehicle might sound louder, but it is rare to get a boost in your overall performance. A few extra HP won’t give you a better acceleration profile. Some people see a drop.
2. The noise in the cabin can be deafening.
It can be a lot of fun to put a straight pipe exhaust on your car or truck. There can also be issues with the noise being so loud in the cabin that it could harm your hearing. It is not unusual for the system to produce an output of more than 100 decibels, so you’ll need to think about how long you have the engine running while you’re driving or a passenger. You might find it useful to keep a set of earplugs around to reduce the risk of suffering from hearing damage with frequent noise exposures.
You can reduce some of the impact of this disadvantage by keeping your windows closed, but that could be problematic on a hot day if your air conditioning isn’t operating – or your vehicle doesn’t come with an A/C feature.
3. This technique is expensive to equip any vehicle.
A straight pipe exhaust system is downright expensive compared to the results you’ll achieve with it. Most vehicles will need a complete change to their entire exhaust structure to make room for the new pipes. If you roll with a top brand for those pipes, then you might pay upwards of $1,000. That’s why the trend is to go with a custom option in this category. Unless you tune the vehicle yourself, you’ll have that expense to worry about too. It is not unusual to be out more than $3,000 before the work is complete – and that’s assuming you do all of the labor on your own.
4. Your vehicle is going to produce a ton of emissions.
Straight pipes can provide you with incredible sounds, but they will also encourage more emissions to enter the environment. That’s why the catalytic converter was introduced to basic vehicular design in the late 20th century. By restricting the flow of gas, the engine doesn’t breathe freely, and that means fewer emissions and lower HP. By removing this element from the system, you’ll restore the performance at the cost of failing an emissions test. Your best compromise here to avoid this disadvantage is to use a cat-back system so that you get the straight pipe setup and the converter at the same time.
5. This option is usually only “cool” to the driver of the car.
It’s really no one’s place to tell someone what they should or shouldn’t run as a package for their vehicle. If you like the straight pipe look and sound, then go with it. You’ll have an aggressive profile that can feel rather attractive. Although there are some exceptions, most of the time this setup is only cool to the individual driving the car. For most people, including car enthusiasts, the idea of running this option is just obnoxious. It’s why you typically see it on the racetrack and not the street.
The issue here is the exhaust drone that you encounter on the highway or going up a hill. This sound gets old fast for most people. Some folks don’t mind this issue and roll with the setup anyway, but there are some options available that can give you potential performance benefits without being overly disruptive.
6. Most cars don’t sound great when you straight pipe them.
When you take out the catalytic converters, then it’s not just an increase in pollution that you might need to worry about with your vehicle. Very few cars actually sound great when you take the straight pipe exhaust option. Unless you have a V8 or better that you drive, then your vehicle will sound more like a lawnmower if you pursue this setup. You might even see warning lights on your HUD if your vehicle runs with O2 sensors, so you’ll potentially force the car to either run rich or lean as it tries to maintain its built-in emissions standards.
You might discover that a well-tuned, open exhaust sounds better on your vehicle that what the straight pipe can provide.
7. It can impact the resale value of your vehicle.
If you decide to straight pipe your car, then you might need to reverse the work one day if you try to sell it. Because the setup is probably illegal where you are, it may not even pass the initial sales inspection during a title transfer. When you add in the fact that the car will smell more like gasoline and exhaust fumes and you might reek of it too, your only option is to work with a future owner who loves this idea as much as you do.
If you want to equip a straight pipe exhaust to anything but a racecar, then you will need to be ready to face some consequences for your setup at some point. There are many barriers in place in the United States and most other developed nations to get a performance vehicle that sounds great, runs fast, and remains street legal. Your best option is to run a bypass system that lets you switch between two exhaust systems so that you can open things up in the country, but then avoid waking everyone up in the morning when you pull out of the driveway.
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.