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I love the farts. But I’d love to know the technical jargon behind why they happen. Is it purely just for sound, or is there a performance reason?
 

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Hint: When you drive a 3-pedal manual, what do you do with your right foot at the moment you up-shift?
 

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Hint: When you drive a 3-pedal manual, what do you do with your right foot at the moment you up-shift?
Let off the gas.

I guess maybe a dumb question now that I think of it. My 135i DCT didn’t make the same sounds.

But my Harley back in the day did.
So is it just a result from the exhaust being so short?
 

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I love the farts. But I’d love to know the technical jargon behind why they happen. Is it purely just for sound, or is there a performance reason?
I love the farts too. But not everybody's. There is debate on why they happen. Some say they are the anal release of exogenous gasses that you have swallowed and by products of digestion. Others say they are the ghosts of poops that never made it out.

Whatever the reason, they are not just for sound. I noticed definate performance increases when swimming or attending business meetings.
 

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I love the farts too. But not everybody's. There is debate on why they happen. Some say they are the anal release of exogenous gasses that you have swallowed and by products of digestion. Others say they are the ghosts of poops that never made it out.

Whatever the reason, they are not just for sound. I noticed definate performance increases when swimming or attending business meetings.
I’m scared for your SO. Haha
 

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Let off the gas.

I guess maybe a dumb question now that I think of it. My 135i DCT didn’t make the same sounds.

But my Harley back in the day did.
So is it just a result from the exhaust being so short?

I don't know the technical details behind the sound - suspect it has to do with momentary fuel cut-off during the upshift, valve timing, and the short, un-resonated exhaust.
And very little to do with digestion. :)
 

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I don't know the technical details behind the sound - suspect it has to do with momentary fuel cut-off during the upshift, valve timing, and the short, un-resonated exhaust.
And very little to do with digestion. :)
Also the blow off valve.
 

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It's venting the suddenly extra turbo pressure. That's normal for all turbos. Most manufacturers and owners want a quiet and boring car so it gets vented silently, and not the SBD type. Alfa and most of us 4C owners want a car with wild character, so the turbo venting is not muffled. There are after-market companies selling kits to convert a quiet turbo into a vocal turbo. It doesn't create extra power or anything, it's just ear-candy and the nature of the beast.
 
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