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I reckon all boxer engines sound similar. Porsches sound more like VW's than WRX's do though.

I'm not sure why the sounds are different, but with a boxer 4 and a v-twin (motorcycle) you get more of a pulse because each half of the engine fires at once. I don't know how that applies to boxer 6 engines because I would have thought the extra set of pistons would interrupt the pulse wave of the other 2.

That also doesn't really explain V8's, which have even more cylinders to interfere with the "pulse" sound, and yet they still sound very "pulsy".

Also, 180 degree parallel twin engines (motorcycles again) sound fairly "smooth" like an inline 4, but a 270 degree parallel twin sounds like a v-twin which also has a 270 degree firing pattern.

thatz coz its a box, and boxes make weird noises?? :confused:

tiny little engine it is, but impressive for little engine, the boxster 2L engine it is..

its like so mini compared to a boxes..to me it doesn't make heaps of power compared to the sky, but in that space it is efficient for power compared to the outside universe.

Subaru (WRX, Forester, Liberty) and VW (Beetle, Kombi, Type 3) engines are the same basic layout and like two40 says have a different firing order to an inline 4. This is why they sound similar if you listen to exhaust noise and not mechanical noise. The VW is extra noisy because it's air cooled and does not benefit from the noise reducing properties of a liquid cooled engine.

Porsche went to a great deal of trouble on the 996 engine (1st production water cooled boxer 6 for them) to retain the "air cooled" sound.

I follow all that, they have a different firing order etc., but they still fire one cylinder per 180 degrees (four cyl four stroke) of crankshaft revolution, just like an inline four, but they sound distinctly different. I cant figure out why, and I haven't heard a satisfactory explanation. For instance, if you changed the camshafts on an inline four to give a different firing order the car (or bike) would sound the same. In fact I believe early Kawasakis had different firing order (1,4,2,3) from Honda (1,4,3,2) but sounded pretty much the same. If it's doing 1000 rpm then it's firing 1000 times a minute at 1/1000 minute intervals regardless of its firing order or configuration. So why does it sound different?

Originally posted by two40

I've never heard a WRX that sounds like a VW.  

VW's sound the way they do because they have a metal chain.

WRX's sound the way they do because like you said, it's a flat four. Crap layout if you ask me. I'll let someone who knows more about it explain.

Don't make me bust out my alfa and show you otherwise Porgie!!

also on JimX,s point, why is it that the more cylinders you have, the smoother the engine (or exhaust note) gets, except for V8's.

For example, a 12 sounds smoother than a 10, which sounds smoother than a 8 which DOESN't sound smoother than a 6 or a 4.

It's a bit hard to compare i guess, cause most people, when they think V8, think of GM/Ford V8's, whereas most 10's and 12's are made by prestige marques. I guess we need to compare a Ferrari V8 to a Ferrari V12 to check properly...anyone care to indulge me? :D

Belly_up, I think a lot has to do with the firing order. The GM Gen III sounds a lot smoother than the previous Holden engine, and the only fundamental difference is the firing order. I think they changed it to smooth out the idle. You can get some of the sound back with a decent exhaust (most I've heard are crap) but it still doesn't sound as rumbly as the old Holden V8's or even the current Ford V8's.

That said, even a "rough" sounding V8 is still quite smooth in a driving sense.

Originally posted by Belly_up

also on JimX,s point, why is it that the more cylinders you have, the smoother the engine (or exhaust note) gets, except for V8's.

cause no one wants a smooth 8. they want a grumpy 8 with a huge cam and blap blap blap idle. muahahaha

ahem, i'll just go to my corner now.:uhh:

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