The Science of Welcome to the "The Lab". "The Lab" is where we'll be conducting intensive product evaluations here at Tuner Performance Reports. Our goal is to provide buyers with the information they need to make informed purchases.

The loss of any of the body's senses results in the other senses increasing their sensitivity. The blind develop their sense of touch and sound to compensate for not having the miracle of sight. The deaf, on the other hand, improve their ability to take in visual input. Lip reading or sign language replaces speech for the hearing impaired. Whether you've recognized it or not, you probably use a number of your senses in selecting aftermarket performance parts for your vehicle. While there's little benefit in tasting and sniffing the muffler, performance exhaust systems are one example of a performance part that should evaluated by sight, sound and touch.

Sight
The looks of a performance exhaust system factor into your purchasing decision whether you admit to it or not. Of course, you are a TPR reader so you're more interested in the "sting" than the "bling." However, parts that do have a quality look and finish may also have a substandard construction. If the manufacturer doesn't care how it looks, he probably doesn't care how well it performs.

With performance exhaust systems different manufacturers use different construction materials. Consider the muffler and piping of the exhaust system. Some are made from painted mild steel, others are made from aluminized steel and still others are made from stainless steel or even titanium. When considering which materials are acceptable for your application you must factor in the climate that your vehicle will encounter and the amount of time that you plan on keeping your vehicle. Both stainless steel and titanium have very good corrosion resistance. These materials make the most sense for enthusiasts that are planning on keeping their vehicle for more than three years or for anyone living in areas that encounter all four seasons. If you live close to the ocean, you should also consider these more durable materials as the sea salt will accelerate the corrosion of an exhaust system. Since the muffler canister receives the highest amount of abuse in the exhaust system, a number of manufacturers will use hybrid material construction to maximize performance and value. In these systems, the muffler is manufactured from stainless steel while the rest of the system is coated mild steel.

In addition to the type of material used, the thickness of the material used should also be considered. While lighter exhaust systems are preferred for those that are weight conscious, systems that use thicker gauge tubing will generally have a more mellow exhaust note and have additional durability. After all, there is more material that must corrode before the system needs replacement.

Sound
The purpose of an exhaust system is to muffle the sound emitted from the exhaust ports on the engine. The challenge of a performance exhaust system is to minimize exhaust noise while maximizing power production from the engine.

If you have ever unbolted your exhaust system or you've had the opportunity to go to an import race, chances are you know how loud an engine can be. Factory exhaust systems will generally place a big emphasis on minimizing exhaust noise. In doing so, the factory system may use smaller than optimum diameter tubing along with a restrictive muffler. The majority of aftermarket systems will increase the diameter of the piping and use a better flowing muffler. Some of the aftermarket systems will have a slightly louder than stock sound while others will let your friends know that you are on the way from five blocks away. This is one area where you should, if you have the opportunity, let your ears do their job. If possible, listen to a similar exhaust system from the manufacturer that you are considering from both outside and inside the vehicle.

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