Do mufflers sound different in colder weather?

It's recently been getting colder down here and it seems as if my magnaflow exhaust sound has become lower, or more of a growl. I bought it this summer so I don't have alot of basis to judge by. I'm no physicist so.. Does cold weather change exhaust sound?

 

That's a good question......

 

Cooler air i believe equals better performance...i have k&n intake,longtube headers , no muffler dumped little before the axle and its louder now that its cooler,

 

Thats what I figured. Mine seems to have just a little more pep in this cooler weather, although I don't really have any validation for it haha

 

Generally untrue. He sweet spot for cooler is about in the 50s.

Freeezing temps will make your car run richer + hurt aerodynamics. Don't forget about winter fuel blends

 

Cool air is denser than warm air, meaning cool air contains more air molecules -- including oxygen -- per volume than warmer air. The engine computer senses the increased oxygen and adds more fuel to keep the mixture correct, which ends in a bit more power. (This means I disagree about freezing temperatures making an engine run rich, but I don't have any evidence either way.) This is comparable to someone who lives at higher elevation ("thinner" air has less oxygen) driving down in elevation to a higher atmospheric pressure where there is more oxygen. For anyone curious, do an internet search for "drag racing high altitude" and you'll see a lot of stories about reduced power output at higher altitudes.

 

I always figured that because the pipes are so cold in the morning that on startup it sounds louder, but after it warms up I really don't notice much difference, but my exhaust is all stock.

 

Mine seems to be like that to. Here in Phoenix its mid 80's during the day buts gets into the 60's at night and it seems a bit louder to me to.

 

It sounds louder for me too (100% stock) but I think it's because the cold start RPMs are higher if the temperature is a lot colder. In the mornings, my engine cold start revs to ~2100 RPM in the middle of winter (35-40F), but only about ~1600 in summer (55-60F).

 

My Flowmaster sounds better when its cold. Although anytime its between 1500-4000 rpm I think it sounds best. Just my $0.02

 

My sweet spot seems to be 2,500-3,000. I think it sounds nice in that range.

 

Oh yeah, thats when its best is right between 2000 - 3000. I was just giving an overall range

 

When air is cold, sound travels slower through it, and colder (denser) air resonates differently. That'll change how the muffler sounds both by how the exhaust behaves inside it (most evident on a cold engine) as well as how the sound moves up into the cabin.

Even a stock muffler gets a bit of a growl on a frosty morning since its resonance-based cancellation is all out of whack

 

So NOW I FINALLY understand why my exhaust sounds raspy if I have to get on it before the engine is warmed up... I try not to, but a rare situation does occur where I have to punch it (for safety or other reason).

 

Lol punching it for safety Nawwwww Son its all about the other situtation Gotta represent

 

i meant leaner. the ECU can adjust the fuel/air ratio to help accommodate,but there are too many variable to make an exact general answer.

you have to take into account the sweet spot for temp (generally about 50s for most modern cars), winter blend fuel, temp and air density.

but what i know for sure is colder the air = the denser the air = negative aerodynamics effect.