Does the winter weather increase exhaust drone? Increase power?

**CharlieBronson08** · 01-21-2013 04:08 PM

I have the Invidia turbo back exhaust in an '08 hatch back. Loved the sound of the exhaust during the summer with windows down. Never noticed exhaust drone too much, or it just didn't bother me. When the weather got cooler in October, I enjoyed what seemed like additional power gains as my spirited pulls seemed a little bit more spirited. All was lovely. (cold air does increase power right?)

But, then I went on a road trip to Pittsburgh in November and hit temps of 40 degrees and even lower. The sound of the exhaust was no longer lovely as my ear drums were about to burst heading up into the mountains in PA. I chopped it up to high altitude and long distance driving at first. However, since December, I've had a ton of exhaust drone; its like a completely different exhaust sound--pitch and tone. I actually roll the windows down in the cold just to eliminate the subwoofer like boom in the cabin.

There must be something with cold-air, humidity, air density or something to explain this. Either that or I'm just trippin and getting progressively more annoyed with my exhaust, and I'm too old to be all race car-ish. Doesn't sound travel more efficiently in the cold? Maybe the air refracts when it hits the warm cabin from the cold outside, changing the note of the exhaust and causing it to have a flatter tone, more drone, and more cabin vibration.

**MainFrame** · 01-21-2013 04:29 PM

cold air = more power.. especially on a turbo charged car

**dloring** · 01-21-2013 07:15 PM

cold air = windows up = drone

hang in there, only 2 more months til spring.

**Eric05mx** · 01-21-2013 07:25 PM

I haven't noticed more drone with the cold temps but noticed more drone if I have 2-3 people in the car.

**Soobvirgin** · 01-21-2013 09:00 PM

Originally Posted by Eric05mx

I haven't noticed more drone with the cold temps but noticed more drone if I have 2-3 people in the car.

Especially if one of them is the mother in law

**wrx650** · 01-22-2013 05:14 AM

For the power increase, does the winter blend of fuel make any difference?

**11blackSTi** · 01-22-2013 05:30 AM

Originally Posted by wrx650

For the power increase, does the winter blend of fuel make any difference?

Winter blends to have higher ratios of oxygen rich compounds, which in theory should increase the octane rating over summer blend. Some peole argue that this brings the stoiciometric values down slightly.

**11blackSTi** · 01-22-2013 05:30 AM

Edit - double post (sorry don't know why it keeps doing this)

***RayfieldsWRX*** · 01-22-2013 05:40 AM

If memory serves, the resonant frequency of a vibrating body (or connected bodies) does change a bit with temperature. I've noticed this in many cars, regardless of windows being up or down, or the presence of my mother-in-law.

**wrx650** · 01-22-2013 05:50 AM

Originally Posted by 11blackSTi

Winter blends do have higher ratios of oxygen rich compounds, which in theory should increase the octane rating over summer blend. Some peole argue that this brings the stoiciometric values down slightly.

That's what I thought. Thanks.

**Axex** · 01-22-2013 09:00 AM

Winter gives more power because the air is denser. Denser air means more oxygen in the combustion chamber and more powaaa!

I don't think Pittsburgh's elevation is that much higher that it would make a difference, but maybe.

In the cold I always noticed my car was louder at idle, especially during warm up, but not really noticeable once driving though.

You mentioned no drone during the summer with the windows down, I had the same thing with my Invidia catback on a hatch (2011). The windows up definitely changes the way it sounds and during the fall it did make it too loud to me. Long distance driving will also make it more annoying and I think there's a good point in there about how once you've had the exhaust a while the "coolness/racecar" effect wears off and it just becomes unpleasant. I have the stock exhaust on now and I don't think it is as bad as people think...

**xFalleNx** · 01-22-2013 09:04 AM

Originally Posted by Soobvirgin

Especially if one of them is the mother in law

hahahaha this is pure win!

**Axex** · 01-22-2013 09:05 AM

Originally Posted by RayfieldsWRX

If memory serves, the resonant frequency of a vibrating body (or connected bodies) does change a bit with temperature. I've noticed this in many cars, regardless of windows being up or down, or the presence of my mother-in-law.

If the air is denser when cold wouldn't it be more difficult for sound waves to travel through, which would make it quieter? I'm sure the humidity plays a hand in this as well. I took an acoustics class, but I wasn't the best student and I don't think I have that book anymore

**wrx650** · 01-22-2013 09:17 AM

Originally Posted by Axex

If the air is denser when cold wouldn't it be more difficult for sound waves to travel through, which would make it quieter? I'm sure the humidity plays a hand in this as well. I took an acoustics class, but I wasn't the best student and I don't think I have that book anymore

I think it would be the opposite. Sound travels faster in denser fluids.

Sent from my iPhone using Tapatalk

**wrx650** · 01-22-2013 09:18 AM

Originally Posted by Axex

If the air is denser when cold wouldn't it be more difficult for sound waves to travel through, which would make it quieter? I'm sure the humidity plays a hand in this as well. I took an acoustics class, but I wasn't the best student and I don't think I have that book anymore

I think it would be the opposite. Sound travels faster in denser fluids.

Sent from my iPhone using Tapatalk