Sound of cars. Why are they different?

I know this is kind of a dumb question but what makes a car sound the way it does? No matter what you do to a car it still has the same basic sound. You can do various things like put a different exhaust on and it may change the volume and pitch or put a turbo on a n/a car which will lower the sound but basically it stays the same. The DSM for example always has the low "fartish" sound. The WRX has a very specific gurgling sound. So why do two, say 4 cyl turbo engines, sound totally different no matter what you do? :confused:

Here's a link to a WRX sound clip:
http://videos.streetfire.net/Player.aspx?fileid=E02D82F8-2420-4928-B911-8528D5491ABF&kw=30&p=0

Its all depends on the engine. You cant easly change the noise of the engine. Now you can change the noise of the exaust to an extent and many ricers do it.

most of it has to do with cam profile, exhaust valve size, number of exhaust valves, and engine layout.

the WRX sounds different because it's a flat 4, not an inline 4

The Boxer engine IMO sounds like crap.

the sound of a wrx is NOT because of the flat 4 set up. its from the unequal lenth header.

if you put an equal length header on a wrx it would sound like a honda.

You have to train yourself to listen for different noises an engine makes sometimes to tell the difference. Changing internal components in an engine for instance will make it sound different. Exhaust notes can be deceiving at times though.

this is my car idling... http://home.comcast.net/~viet_boiiiii/idle.avi
how come it doesnt sound like a i4?

rev
http://home.comcast.net/~viet_boiiiii/tCMagnaflow.avi

cars can change its sound by the modification it has. My tC doesnt sound like them fart cans out there because i dont know why lol.. i seen some other tC's and they do sound like civics. It depends on what u do to your car. Personally i like my car because it sounds like a v8 or wrx at idling.

The most distinct noise from any car I have ever heard, is the sound of a G35/ 350 Z. The engine and exhaust note is very unique, a wailing note; you can tell with your eyes closed. I do know that cams are a big one (Vince's cams make his car rumble at idle like its a V8 or something)

It's sad, I can always hear an eclipse coming a mile away. Just last week I was walking downtown and there's tons of cars. I hear one, I look, and sure enough, it's an eclipse. My car is massively loud, even before the exhaust. Why was it louder? No one knew. None of us could figure it out. Everythings different

I was thinking that cams would be the thing that changed the engine's sound like drdisque and Shpyder said. But when you put like 272's on a DSM/Evo it sounds "lumpier" if you know what I mean but the *sound* is still basically the same. Cams do seem to make sense though. Like on a Vtec engine, the sound is very distinctive especially at high rpm's because of the different cam profile.

What about that equal length header? What if you just took the whole exhaust off the Boxer and the 4g63. Would they still sound completely different? What if you gave them the exact same whole exhaust?

Btw viet_boiiiii, your car sounds really nice.

Btw viet_boiiiii, your car sounds really nice.
Yeah I agree, is that the tC?

My friend and I have been working on his car for a few weeks and finally got the 3" downpipe so we put it on and after working out the spark plug problems, he started the bitch up. Today he called me while I was running and left a voice mail on my phone of the car idling and then revved. Oh damn, it sounded good. It was just coming straight out the downpipe, but MAN, there are some trucks driving around up here that aint got shit on it!

Lol thanks, yeah thats my tC in the vid. I agree with Shpyder on the 350/g35 thingy. I LOVE the sound of their exhaust note and the sound of the wrx. Thats why i bought my car to a shop and personally ask them to custom make me a magnaflow catback to sound like those cars. It came out alright... I wonder why Cams make every car sound a little different.

So why would an unequal length header cause the gurgling type noise on the WRX? Do things like displacement, compression ratio, aluminum/iron block, and head differences also change the sound?

of course all of those things make the exhaust note different but the ej20 and all other subies get their distinctive sound from the header. have you heard the sound of the fx45? how about a 05 V8 audi S4 with an aftermarket exhaust? that is something you will never hear from any other car, just beautiful.

This link provides good information on exhaust system theory, and explains different factors that create unique exhaust sounds http://www.nsxprime.com/FAQ/Miscellaneous/exhausttheory.htm