Can anyone explain this?lol - Alfa Romeo Forum
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Can anyone explain this?lol

Took the car out for a spin last night and the weather turned rather nasty lol
There was puddles the size of swimmin pools lying about in no time.
I have noticed before but last night confirmed that its not just in my head!?lol
The Exhaust seems to be quite alot loader when the road is soaking wet...Really it is lol
Cant think why it should be myself...But can anyone take a guess at it!"?lol
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Re: Can anyone explain this?lol

I'm not a scientist, but is it just the wet surface reflects the exhaust noise better rather than it being dulled by the uneven road surface? Must be some "law of acoustics" to explain this ...
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Re: Can anyone explain this?lol

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Re: Can anyone explain this?lol

your senses are heightened because of the extra adrenaline from driving on wet roads therefore the exhaust note sounds louder, same way you seem to be going faster in the dark......not based on scientific fact, just a guess
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Re: Can anyone explain this?lol

Dunno... I wonder if it's actually the tyres that are quieter meaning you hear the exhaust more? Or maybe, the exhaust itself is colder when the road is wet (with water getting thrown up at it) and that makes it louder? I'm racking my head to work out what happens, I suspect the gas in the exhaust slows down if it gets cool, maybe this changes the effective pulse tuning length of the exhaust ?? There's a phenomenon similar to an organ pipe vibration mode, but caused by temperature differential along a tube; a reigk tube ??? Can't remember, I'll look it up next time I'm in the office.
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