1. an animal that crawled inside
   the catatonic replicator
2. the carbon atomic transferal system
   catalytic converter

The cat or catalytic converter changes especially harmful gases in the exhaust to relatively harmless gases, using precious metals, which is why they cost a pretty penny to replace.

1. catalytic converter
   mid-pipe
2. exhaust manifold
   resonator

The exhaust manifold bolts to the cylinder head, creating an airtight seal so exhaust gases can flow from one to the other without anything leaking.

1. muffles engine noises
   speeds up exhaust flow
2. changes the exhaust sounds
   spins the exhaust gases

You can think of the resonator in your exhaust as a type of echo chamber. It's an essential element to quieting the exhaust, so if you chop it out and replace it with just piping, your exhaust will be louder.

1. the single opening from the exhaust manifold
   It sits in front of the muffler.
2. It sits in front of the catalytic converter.
   the air intake

The exhaust manifold's collectors connect to the different cylinder's exhaust pathways in the head, and those converge, channeling into the single pipe called the front pipe.

1. donut gasket
   header
2. O2 sensor
   mid-pipe

Since the O2 sensor is an essential part of the emissions system for a car, when it fails that will trigger the dreaded check engine light, but a diagnostic will reveal the cause.

1. increase exhaust gases flow
   change the exhaust tone
2. customize the look of the system
   all of these

Admittedly, most exhaust system upgrades don't result in a huge performance benefit by themselves, although they may be necessary for fully realizing the benefits of other modifications.

1. a backpresssure building design
   everything from behind the catalytic converter to the tailpipe
2. a high-flow catalytic converter
   a rearview camera

Cat-back systems are one way to modify the stock exhaust on a car, since most tuners won't touch the catalytic converter, unless they're doing an especially aggressive build.

1. aluminized steel
   tungsten
2. stainless steel
   carbon fiber

Stainless steel resists corrosion, an issue that plagues quite a few exhaust components since they're subjected to road salt and other corrosive factors, plus it's not too expensive.

1. bubbly
   high-pitched
2. deeper and lower
   variable

An H-pipe mid-pipe gets its name for the striking resemblance it has to the letter "H." Not only will it make the exhaust note lower, it usually helps with low-end torque.

1. damage to the muffler
   pinched tailpipe
2. warped exhaust manifold
   worn catalytic converter

While the muffler might be the first place to check for a puncture or rust damage, you should also look at the pipes, since damage on those can have the same result.

1. glue
   gaskets
2. solder joints
   weld joints

Without proper gaskets, exhaust gases would leak out of the different joints in the exhaust system and could potentially enter the car's interior.

1. at the very back
   tucked under the rear axle
2. behind the rear bumper
   it depends on the design

Believe it or not, the muffler on some cars isn't located at the very rear of the exhaust system, and sometimes it can be located near the catalytic converter, so there's really no rule on this one.

1. backfiring
   It smells like something's burning whenever the car is running.
2. flames shooting out of the tailpipe
   hard starts

Over time a catalytic converter can fill up with debris, which not only makes a strong burning smell, but it also cuts the engine power by quite a bit.

1. to sound cool
   boost performance
2. to shed weight
   it's pointless

An exhaust cutout is essentially a Y-pipe where one end of the pipe is open and points toward the back of the vehicle. Mechanically or electronically moving a blocking flange will determine which way the exhaust gases flow, with the cutout pathway usually only used on tracks.

1. It keeps the exhaust moving.
   It prevents backflow.
2. It boosts torque.
   none

Back pressure is never a good thing for engine power, despite what you might've heard in the past, which is why eliminating it is beneficial for performance.

1. bad head gasket
   blown catalytic converter
2. bad O2 sensor
   a bad donut gasket

Donut gaskets sit between different portions of the exhaust piping and other components on the underside of your vehicle, and when they fail, those components will click against each other.

1. when exhaust gases flow from one cylinder to the next
   when heat enters the car cabin
2. a vacuum that keeps exhaust gases moving
   when people steal catalytic converters

If you think that exhaust gases flow at even rates through the exhaust system, the fact is that voids in the flow actually help pull exhaust gases out of the cylinders and into the system, which is scavenging, commonly confused with back pressure.

1. slow down the flow of exhaust gases
   spool exhaust gases
2. spike torque
   nothing

The more bends in an exhaust system, the worse for performance, which is why you'll see exotic cars with almost completely straight exhausts for maximum power.

1. softer
   louder
2. variable
   none

An X-pipe mid-pipe, which has the two pipes crossing in an X-pattern and connecting, will make your exhaust system overall louder and usually helps with top-end horsepower.

1. They look awesome.
   to shoot fire
2. They produce downforce.
   There is none.

While these short pipes that are bolted right onto the engine certainly allow for quick exhaust flow, they also produce downforce to hopefully keep the car from becoming airborne.

1. pipes with zero bends
   pipes made of straight copper
2. exhaust tips that aren't bent
   an exhaust system without catalytic converters

Straight pipe setups have zero restrictions, including a catalytic converter or mufflers. They're louder and the exhaust gases flow unobstructed, but it's usually illegal for street vehicles in most areas.

1. to prevent heat from bleeding out
   to keep it from freezing
2. to fix cracks in the pipes
   it's pointless

If you have an exhaust system that feeds a turbo system, having heat bleed out of the pipe walls isn't a good thing, but in most exhaust setups this modification isn't really necessary.

1. to increase low-end torque
   to prevent the exhaust from hitting a trailer
2. to increase high-end torque
   to make the exhaust louder

One of the points of having a pickup truck is to tow stuff, and if the exhaust exits straight out of the back of the truck, that means it flows right into the trailer. This design prevents that.

1. stuck exhaust valve
   blown catalytic converter
2. cracked exhaust manifold
   bad O2 sensor

You might even think the ticking sounds like an old clock, but it's from an exhaust manifold that needs to be swapped out for something new.

1. 1
   2
2. 3
   4

Some V-6 cars come with a Y-pipe as a way to feed the two sets of collector pipes into a single catback system, which means a single tailpipe.

1. tubes
   baffled chambers
2. fiberglass
   It depends on the design.

Mufflers are designed to reduce the noise levels produced by the engine, but how they do that varies. They might contain tubes, baffled chambers, fiberglass, rock, wool, etc. as a way to deaden the sound.

1. a performance cat
   a performance replacement for the exhaust manifold
2. a performance muffler
   black coating for the exhaust system

Tuners like to swap out the stock exhaust manifold for headers, which allow the exhaust gases to flow faster so the engine "breathes" better. The exact benefit varies by the car and design.

1. increased fuel consumption
   It won't start.
2. lots of backfiring
   shuddering at freeway speeds

The oxygen sensor provides information to the engine ECU, which uses that data to adjust the air-fuel mixture in the cylinders, so a bad sensor could result in too much fuel used.

1. nitrous oxide injection
   blower
2. Roots supercharger
   turbo

Turbocharger fins are spun up or spooled by exhaust gases as they flow through one part of the housing, which in turn draws in fresh air through another section.

1. fuel
   oil
2. enough heat
   centrifugal force

The catalytic converter is usually placed fairly close to the engine so it heats up quickly, but it can't get too hot or it will become damaged, so the engine will cool it off sometimes with an extra-rich air-fuel mix.

1. exhaust valve
   exhaust port
2. exhaust portal
   waste fill

Each cylinder has at least one exhaust valve. It opens after combustion, allowing the exhaust gases to flow out of the cylinder, into the head and then into the exhaust manifold.

1. speed up exhaust flow
   noise insulation
2. create backpressure
   relieve backpressure

Air gap pipes fit over or next to certain lengths of the exhaust system. That extra layer of air shields the chassis from heat as well as keeping the noise level inside the cabin down.

1. turbocharging
   dual exhaust tips
2. supercharging
   larger pipes

Some people like the sporty look of dual exhaust pipes, and a Y-pipe bolted to the back of an exhaust system will give them just that.

1. They only have H-pipes.
   They're longer.
2. Key components are tucked up out of the way.
   They extend out the roof.

The exact design of various off-road oriented exhaust systems varies, but most place the muffler, resonator and catalytic converter as close to the chassis as possible to lessen the risk of damage when driving on a trail.

1. It's welded in place.
   a series of hangers
2. It bolts on.
   a series of magnets

The cat-back system has hooks welded onto it. They fit on rubber hangers, which over time wear out and break. Fixing a sagging cat-back is a relatively inexpensive and simple job.