How come really fast cars have bigger exhaust pipes? is that cos they need them or is it just cos they look?

Question

cos they look nice? are they just for v8s or can anyone get bigger exhausts.

Answer 1

it all just for a stupid image, i think the guys are just trying to compensate for a lack of something else if you get my drift! lolz

Answer 2

larger engines have a greater displacement. this means that when the air fuel mixture is pushed out of the engine, there is just simply that much more. we use a larger pipe to decrease back pressure to enable the engine to breathe.

Answer 3

exhaust are used to direct the flow of the fumes from the engine

away from the air intake valves

so it's not only for show

Answer 4

Fast cars ususally have larger engines that need to breath freely, they take in more air, burn more fuel, make more power and need to expel the exaust faster without excessive back pressure.

Answer 5

The purpose is to allow the exhaust gases to leave the engine easier.  Think of the exhaust pipe as a hose, and the water from the hose is the exhaust gas.  If you have a bigger hose, it's not as hard to get the water out.  It comes out much easier that way.  V8's are the only cars that really need a big exhaust pipe though.  2.5 inches (the standard size diameter of a regular car exhaust pipe) is fine for smaller engines.

Answer 6

Because they have more exhaust to get rid of, a larger exhaust will help the engine breath better on high end speeds. Thats why you see headers on hot rods. You can put a bigger exhaust on any car, but it wont do much good until you build the engine better, in some cases it hurts to do it, engines require a certain amount of backpressure to operate at top effeciency, too large an exhaust wont let back pressure build up, harming fuel economy, and even possibly burning valves and pistons.