If you're looking for more performance from your vehicle, the two easiest components to upgrade are the air filter and the exhaust system.
At the other end of the engine, your vehicle's stock exhaust system typically expels exhaust gasses according to standards of economy, sound, durability, performance and appearance, pretty much in that order of importance.
In other words, stock systems are built inexpensively, give little or no exhaust note, should last for the length of the car's warranty, don't enhance performance, and pay little or no attention to appearance.
That's perfect, if it's what you want.
A performance exhaust system, however, takes care of the same requirements but with different priorities. Performance is at the top of the agenda, followed by appearance and sound, durability, and then economy.
A performance system will be really effective on a turbo car, often adding up to 30 horsepower. On a normally aspirated motor you can still get up to 10 horsepower. Of course, many people just buy them for looks and sound.
The polished surfaces and hi-tech design of these systems are very appealing to those with a stainless steel fetish. However, not all systems are high-grade stainless steel - you have to check for this. The exhaust note is typically quiet at idle, but sporty and robust under acceleration.
Performance systems come with a guarantee that likely outlasts the car.
And, of course, they're not cheap. A full system can cost between $700 to $1500. Somewhat mitigating the cost of a performance system is a possible increase in fuel economy. Some companies do make this claim. However, if your foot's down all the time so you can hear that sweet exhaust note, you'll wipe out fuel consumption gains pretty quickly.
Many performance exhaust systems, such as those from Borla, are made of aircraft quality T-304 steel. It's a higher quality than the stainless systems that come standard on some cars, and vastly superior to lower grade "mild" steel systems. Economy performance systems are often made of "aluminized" steel. Borla, by the way, claims a performance increase of between five and 15 per cent.
In addition, performance systems are built differently - in fact, they're re-engineered for optimum flow of exhaust gasses.
As you know, a vehicle's exhaust system typically snakes its way from the engine back to the exhaust tip. This means the pipe is bent in several places to clear wheels, suspension parts, chassis components and the gas tank. On a standard system, this progressively reduces airflow because the diameter of the pipe is already small, and even smaller where it bends.
On a performance system, you can expect the pipes to be of a larger diameter and mandrel bent. Mandrel bending is a process that retains the diameter of the pipe, even if it's been bent 90 degrees. The goal is almost a "straight-through" design that maximizes flow, permitting more air to enter and exit the motor.
Not all performance systems are mandrel-bent. If you're just going for looks and sound, then this doesn't really matter, but if you want the performance increase then a mandrel-bent system is recommended.
If price is a concern, you don't have to buy the full system. You can just buy a resonated exhaust tip, for instance. It will dress up the back of the car, and add a pleasing note. Expect to spend $60 to $130 for this item.
Or you can get a tip and muffler, maybe in polished stainless steel. This would be welded or clamped on to your existing system. Some companies, like OBX, emulate the look of other manufacturers. They make an HKS-style performance muffler and tip, for instance. Prices range from $250 to $325.
The Full Monty is a complete "cat-back" system. This includes everything from aft of the existing catalytic converter through to the exhaust tip. Typically you'll get mandrel bent pipes, maybe one or more resonators, muffler and tip, and shiny, polished surfaces you could eat from.
The quality, look and sound of these systems vary, and there are numerous manufacturers from which to choose. Borla is popular and high-quality system. Check out the Borla systems at borla.com.
But there are many others. Popular examples are Genie, Sebring, OBX, GReddy, Remus, APEXi, Brullen, Scorpion, HKS, Tanabe, Magna Flow, Flowmaster and Thermal R&D. Edelbrock has systems for small trucks. Borla is now making performance exhausts for big SUVs like the Cadillac Escalade and Ford Excursion.
All these companies have detailed websites with product listings. Some are better known for particular types of cars. HKS and Tanabe, for instance, are popularly used on Japanese cars, Remus on European, but there are no rules.
Installation is often simple, as many manufacturers design their systems to use existing mounting points. I watched a local tuner swap a stock system for a Brullen Cat-Back system on an Audi A4 in about 20 minutes. Of course, some applications will require more time, especially if bolts break or parts have to be welded.
If you're in the market for a performance exhaust, there are a few things to keep in mind. Even though these systems utilize the factory catalytic converter, you should still check that the one you like is emissions compliant. They typically will be, as long as you don't remove the converter, or otherwise tamper with emissions equipment.
Second, will you like the sound of it? A key question. The only way to tell for sure is to hear it on someone else's car. If that's not possible, try going online to carreview.com. Click on exhausts, and read the opinions. Check out the enthusiast magazines, and maybe go to some car shows and meet people who are tuning cars like yours. Be sure to ask about the fit, as well as the sound.
Full performance exhausts typically range from $700 to $1500. A Borla system for a late-model 4.6-litre Mustang retails for $1260 (that's a dual system, of course. A Genie system for a 2000 Integra retails for $785. A Brullen system for an Audi A4 1.8T is $949 and a Scorpion system for the same car is $1400. A Thermal R&D system for the Eagle Talon is $850.
THE POINT: Full performance exhausts make for a great mod--they're easy to install, though not cheap, and make a noticeable improvement in your engine's efficiency.
Mr. X — Bigger, Better, Faster