Cold weather equals more power
 

Last couple cars I had were turbo and supercharged and excessive heat (it gets friggen hot here in Phoenix) and colder weather definitely impacted the power the engine produces by quit a bit. Last night I was out driving the Box and the temps were in the low 40s and it definitely had a little extra kick especially above 5,000 rpms. Butt dyno was saying a good 5 to 10 hp. The last NA car I had was a 89 C4 and it definitely did not get the extra kick the Box seems to have. Have any of you experienced this? Cool dense air makes a difference but just did not expect it to be really noticeable. I assume the on board computer has ability to take advantage of the cooler air.

My butt dyno indicates that a cool drive (40 degrees or so) does indeed produce more power than a hot day driving...

Yes you are right about your observations. Fresh petrol + with cool air + low humidity (<50%) and you are in for a blast with this car.

Mind the cold tarmac surface, tires and brakes mate. It's fun but can be slippery ;)

I think the odds of feeling 5hp extra from a car producing circa 250hp are zero. You're talking about an additional 2% power, roughly. No chance you're going to feel that through your butt.

If you genuinely can feel the difference, it must be way more than 5hp. I think anything less than an extra 20hp you'd struggle to reliably detect. That's still a modest 8% boost in power.

I sometimes feel like cool air is helping, but I think it's mostly the placebo effect!

the cold air , in my opinion can be felt and more so in a turbo car.

A ~5hp gain over a 50 deg drop in temp is believable (say from 80F to 30F). But I doubt that you can feel it.

There is definitely a difference. No doubt about it. Many car enthusiasts claim a difference.

I know I can feel the difference with my 99 HP YZF600 on a cold morning !

My 2000 S seems a little stronger and more responsive.Cold,dense air and A/C in the "off" position. It seems to wail a little louder on my desnorkled intake!

I can feel a difference when I am driving in cooler temperatures, especially at night. It just seems "happier" - smoother, quieter, peppier. I've noticed this on several vehicles, my motorcycles especially. It's not a huge difference, but there definitely is a difference.

My 986 gets a 2-season re-mapping! The MAF also has it's little POT as well.... required by my tuner here to get the car exactly where it needs to be. He is giving a little more air/less gas during hot summer months and LOTs of more gas/more air during cold winter months ;) +562whp

April (hot air tune)
Sept (cold air tune)

Average the same +power all year long. Can't stand the sluggish that this motor suffers during hot summer days.... feels as if the manufacturer A/F curves is preset to perform in northern regions only :/

Both the turbo cars and supercharged cars I've had the difference was big. In the last 12 months we had a huge range in temperatures of low of 19 and a high of 116. The difference with with these difference were in many cases huge. In my three months with the Box the range has 40 to 95. I just came back from a drive and I again stand by the feeling that there is definitely extra power at the top end.

A quite cool -17F the other morning. Butt dyno on my Boxster was too frigid to work, even with heated seat on high.

I wish it was -17. When I left the house this morning, it was -33. Good thing I remembered to plug in last night! Then I tried to roll up my extension cord and the casing snapped. My wheels felt like they were square for the first couple of miles. Jeez I hate this climate.

Don't care about more power....I HATE winter!!!

First salt on the roads now, Boxie is going to hibernate for a couple of months...:(

I might have to disagree that you would not feel a 5hp gain. Some butts are more sensitive than others.

...and on a related note, my mileage has gone down from 25-26 to 22-23 MPG. I can definitely feel the difference in power. Even if it's 5-10 HP, on a 2.5 that's a significant percentage....

I don't notice more power, which is why I've always considered performance mods on this car to be low value proposition, it has to be a signficant increase in order to feel it. And even if you do feel it, after about a week you get used to it. LOL.
I will say that wen ambient temps drop and its dry, the throttle seems much crisper and immediate. Especially with an aftermarket exhaust once you get going.

+1 "my mileage has gone down from 25-26 to 22-23 MPG"
My MPGs always drop in the winter, just like this.

I've seen a similar drop in mileage. I attribute that to the car that longer to warmup and thereby using more fuel during that this period. With my cars I generally see the best mileage when the mornings are warm and the afternoon is not hot enough requiring AC. Once the AC is on and it get real hot mileage drops.