Is it possible to tell the number of cylinders by listening to the engine sound?

[sinopath]

Some people say the 6 cylinder sounds a lot better than the 4 cylinder, so I found two acceleration videos of a 330i and a 440i (both stock exhaust) and found the 6 cylinder has a deeper roaring sound. But then I found a video of M550i (V8) and felt the I6 sounds better. So I wonder are there characteristics in engine sounds that are determined by the number of cylinders? (Update: added reference videos)

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[Burrcold]

You can't tell anything by a video...

[cooolone2]

One man's garbage, is another's castle!

Some like fart cans, some like stealth! Some like the turbo thrush, and others a supercharger whine... To each his own! 4, 6, 8, 12 cylinders, low or high rpm engine, etc., etc., etc.

[jimbobiggens]

This is a v8. If this doesn't get your heart racing you need to check your pulse.

[yco]

actually it is possible.. as long as cars have the similar exhaust setup..

[fastboatster]

Yes, exhaust sound is determined by the number of cylinders AND firing order. Compare cross-plane V8 (most common, almost every domestic v8) and flat plane v8( your Italian exotics):

[freakystyly]

Don't forget about displacement... a 4L V8 will sound different from a 6L V8. The exhaust system is also like a trumpet, different setups play different tones.

[roastbeef]

no. too many variables.

[RM7]

IME, no, not just can you not tell from internet videos, where sound quality and setup (speakers) are not constant, but in person, resonance and other factors wildly change the factors.

I had a 2.0 WRX wagon with a borla "aggressive", I had meant to get the "stealth", but somehow I ended up with the "wrong" one. I was totally happy with it because it was a low growl, crazy low rumble. Totally unlike any WRX/STI I've ever seen(heard) since. No joke, I pulled up to a drive-through window and the attendant is leaning out looking left and right for the "v8 car" making the sound. But, you change out to equal-length headers on a WRX/STI to make more power and then it sounds like a Honda, which sounds like a pissed-off weed-eater.

What I can tell relatively accurately is airplane single-engine horsepower, just by listening to the propeller during takeoff. There's a particular noise the propeller (which is making most of the noise) makes when it's making 300hp and this is fairly consistent. It's a function of RPM and the propeller can only spin so fast and not have the tips going supersonic, so as long as the shape and number of blades is the same, it's going to sound the same.

I've owned several V8s and other engine configurations and I can't say there's any consistency associated with the cylinder count.

[Murf993]

Originally Posted by fastboatster

Yes, exhaust sound is determined by the number of cylinders AND firing order. Compare cross-plane V8 (most common, almost every domestic v8) and flat plane v8( your Italian exotics):

Interesting you used a Mustang Bullet vs Italian exotics, the Mustang GT350 has a flat plane crank to:

[New2Roundel]

Video recordings aside, I think it all depends on the exhaust. IMO, the stock exhaust on my e92 M3 doesn't really sound very v8-ish. I think it could be confused for a 6-cyl car if you're not familar with the motor. Just way too quiet. The more open the exhaust, I think the easier it is to tell what someone's running.

[Humdizzle]

No.

some cars can sound more distinct than others though. I could probably tell the difference between an RS3 (5 cylinder), E92 M3 (crossplane crank), 458 italia (flatplane crank), and GTR (basically a VQ-series), Subaru boxer-4 vs honda inline 4, if they were driving by me at full throttle.

[Rmtt]

Just throw a cam in with a small amount of overlap...

[Chihuahua]

rev it to around 5K and I can definitely tell you if it's a V10. It's unmistakable.

[Alfisti]

Why do Alfa's 4 cylinder engines, especially the 1.7 to bored to 2 litre variety from the early 60's through to early 90's (was the same fundamental engine) sound so distinct? I mean it sounds like a 4 but you know, not ghey.

[Red Bread]

Originally Posted by Alfisti

Why do Alfa's 4 cylinder engines, especially the 1.7 to bored to 2 litre variety from the early 60's through to early 90's (was the same fundamental engine) sound so distinct? I mean it sounds like a 4 but you know, not ghey.

Same reason that Alfa V6's are one of the very few V6's that don't sound awful.

[Pig Farmer]

This guy provides the answer. Kind of painful to sit through the whole video, but it explains the primary and secondary sounds that allow you to distinguish different cylinder count, cross plane vs. flat plane, etc.

[tranquility]

Sound is overrated imo. Sure, if it sounds good why not, but whenever I hear ppl say X exhaust is better than Y, they then compare them head-to-head, and, sure, you can hear the ever-so-slight difference, but if heard by themselves, they both sound good enough and doubtful they could tell unless it's really obvious. Similarly, a 4-banger could be made to sound good and some V12s sound like vacuum cleaners.

Sportscars handling>>>>>>>>>>>>>sound.

[sinopath]

Thanks guys, I'm posting the videos I mentioned in my first post here. I understand it's not fair to compare across brands, but within the BMW brand here are the 330i, 440i, M550i sounds under launch control by the same channel.

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[Thadius]

Listen to a 4 banger indy car and this thread will die

[stein_325i]

Originally Posted by Murf993

Interesting you used a Mustang Bullet vs Italian exotics, the Mustang GT350 has a flat plane crank to:

God the GT350 makes glorious noises. I had the pleasure of driving my friend's through the canyons and honestly its an amazing car.

[Red Bread]

Originally Posted by Thadius

Listen to a 4 banger indy car and this thread will die

Or a V6 F1 car.