Why can't/doesn't the m3 sound like a ferrari?

[Erhan]

Originally Posted by 5erman

if you have enough velocity and enough quanitity of gas,

I think F430 gets like half the mileage of M3. So lets gas burned, so the quantity of the gas should be less too.

And on the velocity part... Maybe I'm confusing 2 things, but isn't M3 exhaust is low-flow?

[FStop7]

If you want to compare a Ferrari to an M3 use the California since they are both front engine with full length exhausts, etc.

[Serious]

Originally Posted by ///Metak

I would like to know how the overall speed of the M3 gases compares to a Ferrari and how this affects the sound that comes out the tailpipes.

*Mods, please don't delete. I am not being sarcastic and really want to learn more about the speed of gases. Thank you.

Would be extremely difficult to calculate exactly since because in addition to the piston expelling the exhaust gases on it's upstroke you also have the vacuum effect due to the other exhaust gas pulses (from different cylinders) as they travel down the exhaust system so as the valve opens the gas is essentially both sucked and pushed out.

In general though the speeds should be fairly similar if RPM is the same.

One of the biggest determining factors of exhaust sound is header material and thickness.

[5erman]

Originally Posted by FStop7

If you want to compare a Ferrari to an M3 use the California since they are both front engine with full length exhausts, etc.

YES woops that totally slipped my mind! But this must obviously be a huge factor as I believe the exhausts have MUCH shorter to travel so they are able to tune exhaust gases at MUCH higher velocity as they exit the pipes where as we have to tune the gases all down the car to the rear and manage to buffer drone v. sound etc.

That would be my guess is why so different or atleast a major factor. good input!

[Doctor J]

if you put a lighter flywheel and an Akrapovic exhaust system (headers + exhaust) -- you would probably get close...

Ferrari California exhaust vid: (won't embed for some reason)

[Serious]

Originally Posted by 5erman

YES woops that totally slipped my mind! But this must obviously be a huge factor as I believe the exhausts have MUCH shorter to travel so they are able to tune exhaust gases at MUCH higher velocity as they exit the pipes where as we have to tune the gases all down the car to the rear and manage to buffer drone v. sound etc.

That would be my guess is why so different or atleast a major factor. good input!

I think you should examine bernoulli's principle which essentially states that pressure and volume are inversely related therefore the gas can only slow if the diameter of the exhaust increases. (i dont know if this is a case with either of the exhausts in the m3 or f430 but I would guess they are both straight through systems, and obviously im ignoring the effects of catalytic converters). The length of the exhaust system shouldn't have any great effect on the velocity of the exhaust gas, but obviously the increased length will further muffle the sound.

The big difference between the m3 and mid engined ferrari exhaust note is engine design (crank design & firing order), engine placement relative to driver, exhaust system material, and exhaust system length.

[JCtx]

I don't understand the attraction of flat-plane V8s (that what the first V8s had, from the late 1800s to the mid 1920s, due to being much simpler -and cheaper- to manufacture); they sound like crap IMO. Maybe just because Ferraris have them, and they're expensive. Anyway, glad the M3 doesn't sound like one . The M3 is possibly the best sounding V8 I've ever heard. And no, I don't like the slow-revving pushrod V8s either, but much prefer the sound of a Vette over a Ferrari V8 any day of the week .

Originally Posted by erhanh

So I was checking the wikipedia

Not a reliable source man. They have wrong the 'firing order' of cross-plane engines: it's LRLRRLRL or RLRLLRLR, depending where you start . Those middle pulses on the same side is what complicates the exhaust on cross-plane V8 engines. A flat-plane engine has even pulses (LRLRLRLR or RLRLRLRL), since it's essentially 2 inline-4 engines with a common crankshaft. The exhaust is very simple; a great asset for tight spaces, like mid-engine cars. And yes, they're inherently imbalanced, so you don't see them in anything other than racing and/or exotic sports cars. That's why Ferrari sourced engines in Maseratis and Astons have proper cross-plane cranks .

Originally Posted by e46e92love

Ask PG, he would know better than I, but a lot goes into low inertia (which leads to fast revving engines, which is what really makes the S65 special, not just high-revving).

Also, from my understanding, counterweights are not needed if the crank is machined right. Its a total design package that you have to look at. But again, I'm not the guy to ask.

You always need counterweights on any 90º V8 since it doesn't have inherent primary balance (it has perfect secondary balance, however). And the larger the displacement, the heavier they have to be. But if the crank is not designed/machined properly, you'd never achieve perfect primary balance (the difference between a Lexus V8 vs a GM one ). But the main factor that affects revs in a street engine (where cost is an object) is CYLINDER DISPLACEMENT. Simple common sense dictates a piston with larger mass and/or stroke will rev less (and slower) than a lighter one with shorter stroke. That's why a 5L V10 will always rev higher/quicker than a similar 5L V8, since it has smaller pistons. Taken to the extreme, that's why an F1 V8 with just 2.4L can rev to 19K rpm. There're a myriad other considerations and variables, but all of the above is just generally speaking.

[Radiation Joe]

Originally Posted by elp_jc

...

They have wrong the 'firing order' of cross-plane engines: it's LRLRRLRL or RLRLLRLR, depending where you start . Those middle pulses on the same side is what complicates the exhaust on cross-plane V8 engines. A flat-plane engine has even pulses (LRLRLRLR or RLRLRLRL), since it's essentially 2 inline-4 engines with a common crankshaft. ...

Jeez,
32 posts before someone actually answers the OPs question. The Ferrari gets it's sound from the even firing order. That's it. Nothing more to add. This is why you can't make a uneven firing V8 sound like a Ferrari.

[Serious]

The other unique thing about the s65 is that it uses a unique firing order of 1-5-4-8-7-2-6-3 instead of the typical BMW firing order of 1-5-4-8-6-3-7-2.

I still haven't figured out as to why they made this change but obviously there is reasoning behind it.

[scheherazade]

Originally Posted by 5erman

How about the Nissan GTR TT V6 that is LOUD and pretty exotic,...

No, it's really not.
It's down right stealthy quiet.

Totally disappointingly quiet when you want to play.
But it's very nice if you are in a hurry and don't want to draw attention.



If you want to do aftermarket stuff to it, then sure, you can make it loud.

-scheherazade

[5erman]

thanks guys firing order makes a lot of sense as that would completely determine exhaust pulses and thus flow character. Cool stuff

To the lad who told me to "examine bernoilles" Well you forgot the most important factor in a combustion engine-energy loss/parasitic loss/friction etc. The longer the gas has to travel the temperature cools which makes it slower, gas loses momentum due to collisions with tubing and friction of gas-gas collissions all signifigantly slow gases so that they are VERY quickly slowed throughout the tubing.

That is why a few companies who make a rear ended exhaust (maybe not for the m3) use a tapering in tubing for the rear section to maintain some velocity near the back.

So yes tubing makes a difference but so does overall temperature and energy of the gas

[White Shark]

C63 AMG sounds like a Porsche Carrera GT (IMHO ) ... Why not M3?

[cotenseto]

Originally Posted by White Shark

C63 AMG sounds like a Porsche Carrera GT (IMHO ) ... Why not M3?

Are you serious? Because a CGT sounds like an F1 car to me in that it not only revs high but it does so with a violent staccato sound.

I don't think the question he's asking is stupid, OP should just have posed it in a different way, such as "What factors influence the sound of varying exhaust types"

c

[SUB-ZERO]

Originally Posted by 5erman

I guess I know the answer to why from the factory an m3 doesnt sound like a ferrari-may be simply too loud. However I have not seen many exhausts that sound like an exotic or atleast most of them do not. I guess I am wondering why in general this car doesnt sound more like a ferrari or exotic. I mean the f430 and many ferraris have had High revving V8 with lower displacement-but even the m3 engine revs higher or as high as those ferrari's and yet not the same crazy sound.

Is there a factor I am missing why this car cannot sound like this? I know "its not a ferrari" obviously but the components to making that sound should be there. Someone please enlighten me as I wonder about exhaust sound capabilities often and to me this car has what it takes to be a ferrari sound a like.

Even the M5/m6 currently can sound pretty exotic and it only revs to 7800. Given its a v10, the high pitch wale is much more dependent on RPM"s IMO--I dont get it!

Google flatplane vs crossplane crank. Also, the P65 version of the M3 engine uses a flatplane crank with a different firing order....sounds more like a Ferrari. However, the flatplane crank increases vibration and that is one of the reasons why it is not used on the street version of the ///M3.


-SZ

[White Shark]

Originally Posted by cotenseto

Are you serious? Because a CGT sounds like an F1 car to me in that it not only revs high but it does so with a violent staccato sound.

Yes...C63 sounds like P-GT to me (at least on the street)...and that's why I love C63.

[Erhan]

Originally Posted by White Shark

Yes...C63 sounds like P-GT to me (at least on the street)...and that's why I love C63.

Well that's obviously because you don't have a mighty ZCP

[DrakeKemper]

Originally Posted by 5erman

I guess I know the answer to why from the factory an m3 doesnt sound like a ferrari-may be simply too loud. However I have not seen many exhausts that sound like an exotic or atleast most of them do not. I guess I am wondering why in general this car doesnt sound more like a ferrari or exotic. I mean the f430 and many ferraris have had High revving V8 with lower displacement-but even the m3 engine revs higher or as high as those ferrari's and yet not the same crazy sound.

Is there a factor I am missing why this car cannot sound like this? I know "its not a ferrari" obviously but the components to making that sound should be there. Someone please enlighten me as I wonder about exhaust sound capabilities often and to me this car has what it takes to be a ferrari sound a like.

Even the M5/m6 currently can sound pretty exotic and it only revs to 7800. Given its a v10, the high pitch wale is much more dependent on RPM"s IMO--I dont get it!

The M3 is a sports car made by BMW, a respectable car for all owners but targeted for the "upper middle". They offer a wide variety of cars and styles.

A Ferrari is an exotic supercar, it is targeted only at the people that can afford them, and although they make three models, they offer only one style of car, the "fuck you, I'm awesome" type.

The stock M3 exhaust has a HUGE "tub" for all of the pressure to resign and swirl around before released, not to mention huge catalytic converters.

I just got X-Pipes, and an exhaust today, and it sounds like a Lamborghini.

[Erhan]

Originally Posted by DrakeKemper

I just got X-Pipes, and an exhaust today, and it sounds like a Lamborghini.

Really? So you made a V8 sound like a V10 (gallardo) or V12 (murcielago)? That's success.

[FStop7]

Originally Posted by DrakeKemper

I just got X-Pipes, and an exhaust today, and it sounds like a Lamborghini.

Originally Posted by White Shark

C63 AMG sounds like a Porsche Carrera GT (IMHO ) ... Why not M3?

Originally Posted by 5erman

How about the Nissan GTR TT V6 that is LOUD and pretty exotic, the last I6 m3/s54 was not exotic but pretty high pitched with the right exhaust.

[socalm3lover]

5erman (OP), good question. Unfortunately, too many children with nothing to contribute but a further demonstration of their inmaturity and lack of manners always seen to think we need their comments. I don't know if M3post has more than their share or not, but sometimes a constructive answer is hard to find.

I had wondered about the flat crank, etc. I have heard V8 sprint cars with a totally different exhaust note and was told that it was the crank. Certainly there are other factors also, but suspect the main difference is the crank as some with constructive comments have stated.

[5erman]

Originally Posted by socalm3lover

5erman (OP), good question. Unfortunately, too many children with nothing to contribute but a further demonstration of their inmaturity and lack of manners always seen to think we need their comments. I don't know if M3post has more than their share or not, but sometimes a constructive answer is hard to find.

I had wondered about the flat crank, etc. I have heard V8 sprint cars with a totally different exhaust note and was told that it was the crank. Certainly there are other factors also, but suspect the main difference is the crank as some with constructive comments have stated.

I really don't get what is stupid about my original question but it seemed many did not like it. However nobody that posted a sarcastic comment recognized all of the legit posts people made and laughed off that this was "common sense" when it surely is not. I guess asking how to tune an exhaust for different sounds may have been a better question but at the heart of my question is truly-with a v8 that revs like a ferrari-to me it COULD likely sound similar.

I think the answer is it can with the right xpipe and exhaust. Not quite but similar. Then the remaining is due to the crank difference and firing order perhaps. However I did find some vids of people with x pipes and exhausts.

That is encouraging that you can sound ilke a lambo-that is the sound I was thinking. To me exotic is prob more what I meant

[Blindside_137]

I think the kreissieg is pretty close. I like the question OP, interesting to see how much variation in sound is among all the different V8's in the world

http://www.youtube.com/user/Gigiti2569#p/a/u/2/

not sure why embed wasn't working