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Exhausting Possibilities

Upgrade your exhaust system for more power and performance

Except for thinly disguised factory-built racecars like the Corvette Z06 or Mitsubishi Lancer Evolution, most automobiles leave the assembly line with engineering built into the exhaust system, suspension, and engine that walks the line between performance and comfort. Factory clutches are meant to engage smoothly and quietly. Installed tires are a balance between a comfortable ride, longevity, and road hugging performance. Suspensions are engineered to keep the vehicle stuck to the road but not sacrifice an acceptable-to-the-majority ride quality. And exhausts are built to breathe efficiently as possible, but still remain whisper quiet even at full throttle.

As hard as it may seem to believe, most folks have no desire to drive to the grocery store sounding like they're heel and toe-ing into the corkscrew at Laguna Seca. The average driver cares more about what color their car is or how many cup holders it has than what kind of lap time it can turn at Road Atlanta or Willow Springs. To the driving enthusiast, this is a sad but true part of the mundane automotive world. Fortunately for those of us who fancy ourselves more Mario Andretti than Ralph Nader, there are good many ways to squeeze more horsepower and sound out of the engines under our hoods. One tried and true method is to get the engine to breathe deeper by way of installing a performance exhaust system.

Make It Yours

Back in the days before super-efficient, computer-controlled engines and 300 plus horsepower motivating nearly everything on the road, an exhaust upgrade was the way to uncork hidden horsepower from an otherwise underperforming engine. This is still true today, even though a modern bolt-on system in a box is a relatively modern innovation. If you had, say, a Plymouth Valiant with a 318, an exhaust upgrade was accomplished by taking a trip down to the local performance muffler shop.

The restrictive factory single pipe exhaust installed with quiet operation and cost savings in mind gave way to wide open pathways to power in the form of a dual exhaust. Larger diameter exhaust tubing and free flowing mufflers let the engine breathe better. A cut here, a bend there, along with a few welds to bring it all together, and that was that. More horsepower and stellar sound was good to go. Out on the boulevard, a wide-open exhaust and a quick tap of the throttle let the driver in the next lane know that you meant business. While performance muffler shops still exist, ordering and installing an aftermarket performance exhaust is easier than ever before.

A bewildering number of companies have made available a mind-boggling collection of part numbers that bolt up in an afternoon with no trip to the muffler shop required. This is a great option for the do-it-yourselfer. Most bolt-on exhaust systems can be installed in an afternoon with no welding required. The principle is the same whether you bolt up your own system or have someone fabricate one for you. Uncork the exhaust bottlenecks and gain a few ponies.

Cat's Meow

If you happen to drive an oddball or rare vehicle for which a bolt-on system does not exist, installing a performance exhaust is still easier than you might think. It's time to go back to the future. Many muffler shops now stock performance mufflers on the shelf from companies like MagnaFlow, along with the regular stock replacements. A competent muffler shop can bend up a custom performance exhaust in the time it takes you to thumb through a magazine or two in the lobby. Like most bolt-on systems, the good majority of these will be fabricated from the catalytic converter out to the chrome tip. Systems that eliminate the catalytic converter are strictly for use out at the racetrack, or on the cruel terrain of the Baja 500. The common myth that catalytic converters rob horsepower is based on the shortcomings of early 1970's-era pellet-style converters and poorly designed proto-emissions systems.

Modern catalytic converters use a free-flowing matrix, which not only efficiently convert smog-causing molecules to friendlier versions, but also offer very little in the way of exhaust flow restriction. The performance gain from catalytic converter-back exhaust comes from uncorking any restrictions in the exhaust system, and opening up the muffler with a free-flowing internal design. The same things that make a muffler quiet also act as a restriction to exhaust flow. Keep in mind that while larger-than-stock exhaust tubing will help the engine to breathe; too large a diameter will deliver diminishing returns. A two-liter engine has a displacement the size of a two-liter soda bottle, and simply does not have any use for a five-inch diameter exhaust pipe. Other than that, there is no downside to a performance exhaust—just the uncorked sound of a happy engine, more power, and a smile on the driver's face.

Resource

http://www.magnaflow.com/