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Replacement Mufflers
If your car is starting to rumble and roar
like a drag racer, it’s probably
time to
do something about your muffler.
For many
consumers that means pulling
into one of
the well known replacement muffler
shops
(such as Midas, Meineke, CarX,
or Merlin’s
Mufflers) and making a best guess
of what
options are really important.
However, a
few basics about mufflers can
help you make
a more informed decision.
The original muffler on your
car was intended
to make your car quiet—with only
secondary
concerns about maximizing engine
power, fuel
economy, and durability. When
the original
muffler eventually rusts out
(and it will
after a half dozen years or so),
you will
have the opportunity to select
a replacement
that better fits your needs and
desires.
Several features about muffler
design and
construction underlie the wide
range of mufflers
that are available.
- Baffled or flow-through design. There are
two basic types of mufflers. The most common
style has internal baffles that force the
exhaust gases to bounce back and forth inside
the muffler shell to dissipate energy that
is left over from the gas explosions that
occur in the engine cylinders. The trade
off to taming the exhaust stream in this
way is that the baffles restrict the flow
of the gases on their way to the tailpipe
and cause "back pressure" in the
exhaust line that adversely affects the efficiency
of the engine itself. To avoid this, an alternative
design allows the exhaust gases to pass straight
through the muffler in a perforate pipe that
is surrounded by sound absorbing material,
such as fiberglass. This design is a bit
noisier but it helps engine performance (and,
thus, they are often called “performance
mufflers”). Increases in horsepower and fuel
economy can be quite real.
- Material of construction. Exhaust gases are
extremely corrosive and eat away at the muffler’s
innards even faster than road salts and other
environmental hazards attack the shell from
the outside. Auto manufacturers have decided
that it is not cost effective for them to
strive for longer muffler life—to the disadvantage
of people who keep their cars longer than
average. Standard mufflers are made of steel
with galvanized or aluminum coatings, but
premium mufflers use stainless steel (which
never rusts). Not surprisingly, they are
more expensive.
- Sound options. While the fundamental purpose
of a muffler is to dampen the noise of the
engine exhaust, absolute silence is impossible
to achieve. So, if there will be residual
noise anyhow, why not tune it to a particular
style? Accordingly, mufflers can be distinguished
by the character of the sound they produce—leading
to a unique vocabulary among muffler specialists
that rivals that of wine connoisseurs; terms
include throaty, deep, aggressive, and bold.
Not to be overlooked in choosing
a replacement
muffler is what guarantee comes with it.
Many manufacturers or installers offer to
replace the muffler with a new one for the
life of the car—as long as the present owner
keeps it. If you're planning on selling your
car in the next year or two, it probably
isn't worth paying extra for this guarantee. |
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