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I expect the answer is miniscule, but doesn't producing noise waste horsepower?
 
Reminds me of a drive up form FLA one year.. We had turned of the highway to make a 'bathroom break' and at the light, in traffic, beside us was a convertible.. Top down, young-ish guy, and blaring some metal-rap-crap.. the scenario played out in my head:
me: "Hey, Dude!"
him, turns down the tunes: "Huh, what"
Me with a smile, and some obvious interests: "that's pretty rugged, who is it?"
Him, smiling: "Its the Otis & the Four ruggers"
me: And I guess they're best loud, eh,?"
him: "Yup!!"
me: "so, why the [firetruck] do you think we all need to hear it?!"

cheers from the the other drivers stopped at the light!
 
Living in suburban Southern California we are treated to three layers of insult; 1) Fart cans. 2) Harley pipes, and 3) over-sensitive car alarms that go off when either 1 or 2 pass down our residential street. Oh, and there is a #4...the wannabe drifters that fly around the corner and crash into the curbs (at least we get the satisfaction of their destroyed rims). Maybe these are the thieves who keep stealing our catalytic converters?
 
Yes, several times, and TF rails and TF funny cars don't cruise the neighborhood. However my cousin's husband used to compete in TF back in the late 60s and 70s, he brought his TF rail to a City clelebration parade and towed it through the parade route.. He fired it up in front of the local courthouse. The first known cacklefest with predictable results. Race cars weren't allowed in the parade for some time after that.
 
Yeah, this whole thread is a "get off my lawn" rant. It's been entertaining watching it shift from "those loud cars suck!" to "these loud cars are awesome!"

They're all loud and annoying to people who like peace and quiet and dream of having decibel triggered/oriented turret-mounted RPG on top of the house.

Written by someone who likes loud sparky motors...
 
They're all loud and annoying to people who like peace and quiet and dream of having decibel triggered/oriented turret-mounted RPG on top of the house.

Ooooo! I hadn't thought of that one! I'm keeping it!
 
Yeah, this whole thread is a "get off my lawn" rant. It's been entertaining watching it shift from "those loud cars suck!" to "these loud cars are awesome!"

They're all loud and annoying to people who like peace and quiet and dream of having decibel triggered/oriented turret-mounted RPG on top of the house.

Written by someone who likes loud sparky motors...
don't give me any ideas LOL
 
I expect the answer is miniscule, but doesn't producing noise waste horsepower?

It's all about converting potential (chemical) energy to kinetic energy (mechanical, heat and sound are all kinetic):

1. movement of the piston - that's really the one we want and that causes vehicle movement
2. movement of exhaust gas (including heat and ejection) - kind of wasted energy but necessary for 1.
3. movement of "static" motor parts (vibration and heat), and surrounding air - this is where sound is from - kind of wasted energy but necessary for 1.

So noise is wasted energy, but "directing" that energy to piston movement instead isn't really possible. Potential energy gets converted into the various forms of kinetic energy as it pleases with engineers having limited contol over how much of each kind. But yes noise involves a very small portion of overall energy. Moving eardrums as opposed to tons of steel.
 
It's all about converting potential (chemical) energy to kinetic energy (mechanical, heat and sound are all kinetic):

1. movement of the piston - that's really the one we want and that causes vehicle movement
2. movement of exhaust gas (including heat and ejection) - kind of wasted energy but necessary for 1.
3. movement of "static" motor parts (vibration and heat), and surrounding air - this is where sound is from - kind of wasted energy but necessary for 1.

So noise is wasted energy, but "directing" that energy to piston movement instead isn't really possible. Potential energy gets converted into the various forms of kinetic energy as it pleases with engineers having limited contol over how much of each kind. But yes noise involves a very small portion of overall energy. Moving eardrums as opposed to tons of steel.
You should see how much forward thrust John Force got with his headers when he experimented sweeping them back instead of up. Now there is a limit on swept back headers.

https://www.racingjunk.com/news/adios-nhra-funny-car-laid-back-headers/
We used to fire up a AA funy car in the driveway, and I used to think my Kawasaki triple two stoker with stingers on the chrome expansion chambers sounded good. It would piss me off today if the neighbor did that and ran one up and down the street. I'm getting old:cool:
 
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It was!! The ear splitting sound of a 750cc two stroke and the smell of Bel-Ray oil is not easily forgotten

Tell me about it. I build an RD400 Cafe Racer with Boyesen reeds, chambers, trimmed guards, clip ons and rear sets. Solo seat and air suspension. Great race bike, but I commuted on it as well. Cost me more in fines than it did to build...
 
I expect the answer is miniscule, but doesn't producing noise waste horsepower?

My experience is that noise represents horsepower. That is why I like rockets and drag racing.

More power=more noise.

The ground shaking violence during a nitro car launch makes me happy.
 
Harley Davidson is famous for the sound of their engines so I was surprised to find out they made electric motorcycles too:
 
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