Humid weather effect on performance
 

Yesterday morning on a clear, quiet drive to work I noticed something spectacular about how my fr-s was feeling. Everything about the engine and throttle response was crisp, accurate, and buttery smooth. As my drive went on I put more and more focus on the rpms and just how quickly the needle punched through each mark on the tachometer.

It was a little after 6 am when I hit the road and the air was so clean, cool and completely still. I live on the coastal region in Virginia and generally we have a pretty fair amount of humidity... on a hot mid-summer morning you can seemingly break a sweat before the sun even peeks. Being so caught off guard by the increase in performance on the pants dyno, I reminded myself to compare the ride home around 4pm with plenty of hot air and a more humid atmosphere. Sure enough things started to bog down a bit. The throttle response was not as sharp and there were definitely moments where the revs seemed to choke(not talking about torque dip). It just felt like the 86 had run a 5k and was gasping for air, compared to in the morning where it was free to be out of its own way.

In an attempt to conclude the weather as the factor, I did check the temps on the google weather app, and oddly the humidity reported contrarily at 89% humidity and 64 degrees in the morning; and only 76% humidity and 71 degrees during the ride home, even though there was a brief shower and noticeable moisture slightly before that drive. But I have no how accurate or real-time the data is for the app.

So have any members experienced this same behavior in humid climates? And are there any tricks or minor mods to help circumvent the engines response to hot air and make it more adaptive?

Temps make a BIG difference. Humidity does too but not as much. I notice this all the time

With that small of change in humidity and temperature ........ I think your pants dyno is ah messen wich ya .........;)


humfrz

you can certainly tell difference between the dog shit hot texas summer days and a cool winter day on how the car breathes. but i cant perceive more humid to not, 400 miles from coast doesnt get quite as balmy.

Go away, you live in Calgary...It's a desert. Do you know what humidity feels like? lol

My Fr-s doesn't like hot humid days and refuses to play. ;)

LOL to be honest... no hhahahahaah!

Well, picture what you feel like after you get out of the shower (Wet)

Sexy?? :iono:

haha!! :clap:

I definitely feel a difference in varying conditions of temperature or humidity.

I live in the SF Bay Area south of San Francisco. What I've noticed is that warm, mild humidty is the best condition for the car. Warm meaning 75 degrees. I've never driven the car in super hot weather (90 degrees +) but I've driven it in cold mornings around 40 degrees and it felt like crap.

I did drive it one night with a moderate humidity with the temperature around 65 degrees and it was beautiful.

Spend a week in Asia during the mid summer and you will know what real humidity is.

So the consensus is that hot air (and not specifically humidity) is harder on the engine? What exactly causes the engine to choke on hotter temps? I've heard of track days getting ugly if the engine goes over temp but what is going on that makes this the case?

Oh, I reckon that on hotter days, an engine runs a tad bit hotter and the air contains less oxygen.


humfrz

Also, the ecu doesnt like high iats. In south fl the car feels respectable in early am and relative dog shit in the afternoon.