Comparing an aftermarket Mustang exhaust system to your stock parts is like comparing a mansion to a motel. Sure, you can sleep in both of them, but everyone knows which will be a better experience in the long run. If you're thinking about replacing your Mustang exhaust with some parts from Lethal Performance, you'll need to know about some of the main components that make up an exhaust and how you can get the benefits suited to your specific tastes. The experts here at Lethal Performance have created the ultimate guide to Ford Mustang exhaust systems so you can recover your power from your engine, meet legal vehicle requirements and enjoy all the performance benefits along the way. Keep reading to find out more.
The Front End of Your Mustang Exhaust System
A new performance Mustang exhaust system is one of the most common Ford Mustang upgrades, especially for car enthusiasts looking for their first performance upgrade. It's easy to see why aftermarket Mustang exhaust systems are so popular – they can improve your performance, sound quality, efficiency and fuel economy after an afternoon of installation. When looking to replace your Mustang exhaust system, you can either opt to install a complete kit, replace just one component or mix and match different parts to tailor your setup to your exact needs. For now, we'd like to focus on the two standard front-end components you'll replace if you choose to install your parts individually.
In your Mustang, the exhaust manifold connects to the exhaust ports of your engine to funnel exhaust gases from the cylinders to the mid-pipe. The manifold is the stock name for a header – an aftermarket component that exceeds a stock manifold across the board. Typically, your stock manifold comes with several holes that merge into one common chamber. Aftermarket headers generally have tubes that curve to join the exhaust ports to the pipe, allowing exhaust gasses to gently flow into the pipe rather than slamming through the ports. Mustang exhaust headers typically come in two different styles: shorty headers and long tubes.
- Shorty Headers: Shorties are about the same size as your stock exhaust manifolds. They'll work in tandem with your stock mid-pipes as well as standard aftermarket mid-pipes. This type of header is a direct replacement for your stock manifold and does not require any extra parts or a tune to work to total efficiency. Shorty headers are an excellent upgrade for the average daily driver, giving a boost in horsepower and torque, specifically in the mid-RPM range.
- Long Tubes: Long tube headers are too long to bolt up to a stock mid-pipe, so they require a shorty mid-pipe to maintain a consistent exhaust length. They're typically used on the track rather than the street, and they generally provide more horsepower and torque when compared to shorty headers, seeing the most performance gains in the mid-low to mid-high RPM range. But keep in mind that long-tube headers cannot be used with a turbocharged motor and will require a tune – if you're going to be installing more performance upgrades, shorty headers may be the way to go.
All Mustang exhaust systems include a mid-pipe for the exhaust gases to travel after they leave the manifold. You have an option of choosing from X-pipes or H-pipes in either standard or shorty lengths if you're looking to install this Ford Mustang upgrade. "X" and "H" refer to the shape of the mid-pipe – the length you choose will depend on the type of aftermarket header you have installed. As mentioned above, long-tube headers will require a shorty mid-pipe, while shorty headers need the standard length. If you're keeping your stock headers, you'll be looking at a standard length for these Ford Mustang upgrades.
An X-pipe for your Mustang exhaust can provide an immediate boost in horsepower for your engine, typically slightly more than the H-pipe design. This is because X-pipes offer a smoother path for the exhaust gases to flow, letting your engine breathe just a bit more. Horsepower isn't the only thing affected by installing new mid-pipes on your Mustang exhaust system. Typically, X-pipes affect the sound of your Mustang by giving it a higher-pitched, raspy note, while H-pipes encourage a deeper rumble. It seems that most car enthusiasts prefer the deeper, more aggressive tones an H-pipe can provide and don't mind sacrificing a few increments of horsepower. Still, sound is just a matter of taste. While some vehicles also offer a straight mid-pipe, we highly recommend against this for your Mustang. Mustang exhausts were designed with a crossover to help equalize exhaust pulses and backpressure. If you install a straight mid-pipe, you'll destroy your engine's performance capabilities (which we know you really don't want to do).
There is also one more critical factor that you need to know when looking at a mid-pipe for your Mustang exhaust system. All stock mid-pipes come outfitted with a catalytic converter to remove contaminants from the exhaust and make your vehicle emissions friendly. When you choose a mid-pipe for your Mustang exhaust, you'll have an option to select from off-road or catted mid-pipes. If you're looking to upgrade your Mustang exhaust system purely for racing applications such as track and drag racing, off-road mid-pipes are your best option. Your Mustang will get an even stronger boost in horsepower and torque by removing the restrictive catalytic converter, perfect for blowing past the competition. If you're going to be driving your Mustang daily, just stick with a catted mid-pipe. Not only will you not be able to pass an emissions test if your state requires one, but it's also illegal to drive a street vehicle that has this part stripped out. If you get pulled over and an officer decides to check for your converter, you're going to get a hefty fine. Catted mid-pipes still offer a significant boost in horsepower and torque, and more importantly, they keep your Mustang legal to drive wherever you want.
Cat-Back & Axle-Back Mustang Exhaust Systems: The Back End
Now that we've covered the front end of your Mustang exhaust system, it's time to focus on the back end. You have two options when choosing these Ford Mustang upgrades – cat-back and axle-back exhausts. Both of these work well with all types of headers and mid-pipes, so it's really up to you to decide which you'd prefer. It's common for most beginner car enthusiasts to focus purely on these components when upgrading their Mustang exhaust systems for this reason. (Also, they're incredibly easy to install.)
Cat-Back Mustang Exhausts
A cat-back exhaust system begins at the catalytic converter and runs back to the rear of the car. Cat-backs are typically sold in kits comprised of a performance muffler and tailpipes. Cat-back Mustang exhaust systems are designed to improve your exhaust flow further due to their mandrel-bent piping, freeing up extra horsepower and torque. In addition to this, cat-back exhaust systems are known to enhance the sound of your Mustang, giving it a deep, aggressive rumble upon startup and acceleration without requiring a tune. While horsepower and torque gains vary from manufacturer to manufacturer, you can typically expect anywhere from 10-20 horsepower and torque gains when installing a cat-back Mustang exhaust system.
Axle-Back Mustang Exhausts
An axle-back Mustang exhaust system is essentially just the muffler, beginning at the rear axle through the back of your Mustang. Axle-backs are the last component of an exhaust system and primarily affect the sound more than anything else. While they offer some performance gains, these Ford Mustang upgrades are made to influence your exhaust notes. Typically, they only can add less than five horsepower on average but are still a significant improvement over your stock system. Different systems will offer different exhaust notes, so it's best to do your research before purchasing one. That being said, axle-backs are generally not as loud as cat-back exhaust systems or headers.