Originally Posted by ramuman
The difference is largely due to the exhaust. If you have just the engines, it's really hard to distinguish. A partner at my previous company had an E60 M5 and I had my E92 M3. The engines themselves sounded fairly similar. One of the biggest clues was the S65's unmistakable firing order on startup. The exhausts were completely worlds apart though.
A lot of the theatrics associated with V10s and V12s comes from the exhausts they're usually paired with. I will admit there is a difference in the engines themselves, but I6s inherently sound very very similar to V12s.
Tell me what this engine is (I6, V8, V10, V12, etc.) - it's on a dyno with no exhaust (jump to 55s in):
and another guess (hump to 20s in; this is with exhaust on a different car):
(jump to 50s in)
and one more (again with exhaust):
and one last one just for fun:
All of these are about as accurate as possible and from outside the car - the volume isn't balanced though since I was lazy, the last three are on actual cars, the first is on a dyno. All from engine types described in the last 3 pages of this thread and all are 4 very different engines, but all from modern production cars.
The first one is very weird. I listened to the entire clip and at 30 seconds, it has the rumble of a V8. Sounds just like the E9x M3 if I had to guess. But after 50 seconds, I can't really say. It's very hard to tell.
Second one has the unmistakable sound of an F8X M3/M4 at cold start. Sounds just like my coworkers M3 -- it has that "rattle" sound on startup.
Third one is obviously an Aventador. That signature V12 sound on the Aventador is very distinct. I've heard many exhaust clips online.
Last one had me stumped initially cause from 3s to 5s, it has the sounds of a high-pitch V10 accelerating, but rather muffled. Then as the pitch gets higher in frequency, it obviously becomes an electric engine. So, knowing you, that's one of the Model S'.