Big Newbie Question

[dx316gol]

What is the difference between a exhaust and muffler? What do both do? I know exhaust makes it louder, but what does muffler do?

[chameleon]

dx316gol, a muffler is part of an exhaust. When the engine burns gas, the exhaust fumes go through quite a journey before they exit the car's tail pipe. The first place the exhaust fumes go is out the cylinder head, into a header. A header is basically a pipe that comes off each cylinder and collects all the individual pipes into one single pipe. Then, this one single pipe goes into a catalytic converter. The catalyst inside the catalytic converter is what makes the exhaust fumes less harmful to the environment. After the catalytic converter is done reducing the harmful emmisions of your car, the exhaust pipe will then go into a muffler. A muffler is what makes the volume of the exhaust less loud. Mufflers can perform this function in many different ways. I believe that the stock muffler on the car is probably the kind that is packed with fiberglass, and the exhaust being forced through it absorbs the sound. Then the exhaust leaves the muffler and exits out the rear of the car.

So when you say the word "exhaust" you are talking about all of these components that are on your car(a header, a catalytic converter, a muffler, and exhaust piping). The part that has the biggest responsablility for making the exhaust sound louder is the muffler. When you buy an aftermarket exhaust, like a TRD, Blitz, TRM, ect., what you are buying piping that goes from the axle to the muffler, a new less restrictive muffler, and piping that goes from the muffler to the back of the car.

[GeeTeeEss]

Originally posted by chameleon
. The first place the exhaust fumes go is out the cylinder head, into a header. A header is basically a pipe that comes off each cylinder and collects all the individual pipes into one single pipe.

Actually this is an exhaust manifold. A header is 4 (or whatever amount of cylinders) seprate pipes that come off the head. Aftermarket headers exist but don't come w/ the Celica.

[chameleon]

Actually, the Celica does not come with an exhaust manifold, it comes with a Header.

[da wacky paki]

Exhaust manifold = Header
or am i wrong?

[chameleon]

No, your not wrong da wacky paki, a header is an exhaust manifold, but there are different styles of exhaust manifolds. The most common type is where all the exhuast from the cylindars is expelled into one big cast chamber that bolts onto one pipe that continues to the rear of the car. Another style is the header style, where each cylindar has its own exhuast pipe that collects into one big pipe, which in turn connects to the pipe that continues to the rear of the car. When GeeTeeEss said that the Celica doesn't come with a header, it comes with an exhaust manifold, he was reffering to the common style manifold where all the exhuast from the cylindars goes into one chamber, not the header style manifold, but the Celica does come with a header style manifold. But you are right, they are all exhaust manifolds.