Does a cam change the volume of an exhaust note?
air carries waves, but waves can also travel in the vacuum of space. Yes, a higher density helps waves travel further, but I don't beleive that a cam changes the density of the expelled air by that much at idle and part throttle.
If you look into header design, you'll see the wave issue and tuning the headers to certain rpm ranges. The waves are related to the cam timing which in turn influences the power band.
If you look into header design, you'll see the wave issue and tuning the headers to certain rpm ranges. The waves are related to the cam timing which in turn influences the power band.
So wait... it just occured to me that a few of you have proposed that the theory goes as follows:
More air + more fuel = more loud...
but then wouldn't FI superchargers be louder since they are doing the above? It seems to me that nobody with a supercharged setup has reported a louder exhaust note. (just belts and induction being loud)
(obviously, turbo has its own effect on exhaust note, being attached to the exhaust and all)
So is a supercharged FI setup louder, or is the theory of more A+F being louder bunk?
More air + more fuel = more loud...
but then wouldn't FI superchargers be louder since they are doing the above? It seems to me that nobody with a supercharged setup has reported a louder exhaust note. (just belts and induction being loud)
(obviously, turbo has its own effect on exhaust note, being attached to the exhaust and all)
So is a supercharged FI setup louder, or is the theory of more A+F being louder bunk?
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This is a very broad way to look at it but, think of a top fuel dragster and a pro street dragster. Just because a car has a supercharger doesn't mean it is more powerful than a n/a car. Also the exhaust has a lot to due with the noise of a car. If you had a car with a s/c and a n/a car and they both had the exact same exhaust and the n/a car had more hp then the s/c car would be louder. You have to take into consideration that a car with 300 hp and a car with 320 hp aren't going to be that much different if the exhausts are exactly the same. But a car with 200 hp and a car with 400 hp you will definately hear a difference in the noise level with the exhausts being exactly the same.
I guess what I mean is, if one recorded the exhaust note of a car, then supercharged it and recorded the new exhaust note, would the new note be louder? (excluding induction and belt noise)
I believe the exhaust note and loudness has alot to do with when the exhaust valve starts to open. The earlier the valve opens the louder it is going to be. More of the pressure from within the cyclinder is escaping creating a louder noise. Although I would not describe it as noise....more like music to the ears....
