Effects of humidity?

[Quadcams]

Originally Posted by troppo

In a nutshell, humidity has very little effect at low temperatures. As temperatures increase, the effects of humidity increase exponentially.

.

That is one thing I have definately noticed about humidity as the temp rises humidity plays a bigger factor.
I have raced in 36c with very high humidity 3-4mph down and about 3-4 tenths slow but in same temp (36c) but very low humidity 1mph down and only 1-2 tenths slow.

[brenx]

Originally Posted by troppo

Check your slips. I have a hunch the increase in humidity coincides with a decrease in temperatures. Cooling air means relative percentage will go up, although actual volume of moisture doesn't change much at all, unless it cools enough too reach 100%, then moisture starts getting forced out of the air as dew or condensate.

Temps have also decreased as I've already stated.

[Quadcams]

Originally Posted by troppo

unless it cools enough too reach 100%, then moisture starts getting forced out of the air as dew or condensate.

Happens alot a WSID on wednesday nights in the winter months

[northey]

Humidity and temperature both have an effect on engine power, sometimes a huge effect. Engine tuners need to take all this into consideration when tuning at the track.
Another likely scenario from a car running quicker in humid air is that the track has more rubber laid during the course of a meeting. The traction always improves from that. It doesn't matter whether it's circuit or drags, the more rubber laid the grippier the track is and the quicker the car will go.

Sometimes when the air gets really cold and the engine makes good power you can overpower the track. It can get a little slippery as the the car starts turning the tyres out from the startline. You can hardly feel the tyres slip but it drops a couple of mph off very easily when it happens.
The end result is that the driver thinks the car is losing power and they change the tuneup.

[Stav]

Originally Posted by northey

Humidity and temperature both have an effect on engine power, sometimes a huge effect. Engine tuners need to take all this into consideration when tuning at the track.
Another likely scenario from a car running quicker in humid air is that the track has more rubber laid during the course of a meeting. The traction always improves from that. It doesn't matter whether it's circuit or drags, the more rubber laid the grippier the track is and the quicker the car will go.

Sometimes when the air gets really cold and the engine makes good power you can overpower the track. It can get a little slippery as the the car starts turning the tyres out from the startline. You can hardly feel the tyres slip but it drops a couple of mph off very easily when it happens.
The end result is that the driver thinks the car is losing power and they change the tuneup.

Yes I believe that.92% humidity on my last run and later 100% did not make for traction.

[FS5]

i was just going threw my wod of time slips i have here from willowbank .i have to agree that the RA levels play a big part in how your car runs,you definately want RA levels below 1000 to real off some decent times.i don't think the humidity plays a big role when the temps are lower .like quadcams said when the temps are high though thats a different story it just kills it ,feels like you've left the handbrake on or somethin.
one thing i have found is that its a lot harder to get the car to hook up off the line in summer when the weather's hot compared to when its cooler in winter.

[Quadcams]

Originally Posted by useless

Yes I believe that.92% humidity on my last run and later 100% did not make for traction.

Stav take into account I have raced at WSID in winter with 100% humidity and track conditions were awsome (straight after big meet), in other words depends if the track has been preped properly for the street meets and when you were out there last a few others commented how bad the track was that night.