Drag racing in the heat/humidity - Subaru WRX Forum
 
LinkBack Thread Tools Display Modes
#1 Old 07-24-2008, 09:27 PM
WRXtuners Member
 
zmanoside's Avatar
 
Join Date: Sep 2006
Location: North Carolina
Posts: 430
zmanoside is a helpful contributing member
Drag racing in the heat/humidity

So I went to the track 2 weeks ago, 05 STi stg1 and pulled a couple 13.2's. Weather was mid 80's. Tonight, stg 2 I couldn't pull better than a 13.4!!! I knew it was damn humid tonight, so I checked the weather online when I got home and at the time I was running it was 92 degrees with 94% humidity:eek: It seemed like my car was def not running great/ slower. So what is worse, the heat or the humidity??? And how exactly do these factors effect HP and 1/4 mile times? I know the colder the air the better, but how does humidity affect the times??

Z

12.7 @ 109
zmanoside is offline  
Sponsored Links
Advertisement
 
#2 Old 07-25-2008, 05:40 PM
Moderator
 
mosc's Avatar
 
Join Date: Mar 2005
Location: Pennsylvania
Posts: 6,481
Images: 7
mosc is a helpful contributing member
Garage
humidity reduces the density of air similar to altitude or temperature. However, it's not very linear. The hotter it is, the more water is required to reach a given "percent humidity". Having 94% humidity when it's 50 degrees outside is not really that significant but as it gets hotter (say, the 90s), it becomes more and more significant. So, humidity is bad on a hot day. Really bad on a really hot day.

04 STi 16G powered lagless fun
04 WRX: SOLD
mosc is offline  
#3 Old 07-25-2008, 10:19 PM
WRXtuners Member
 
zmanoside's Avatar
 
Join Date: Sep 2006
Location: North Carolina
Posts: 430
zmanoside is a helpful contributing member
Yeah it sucked pretty bad. I started doing some research myself on the web on drag racing and weather conditions, I found that the barometric pressure has the most effect on racing, followed by temp and then huidity. Hard core bracket racers actually buy "weather stations" small electronic devices that mesure all of these factors and more to determine what their car will run on a specific day in specific weather. I was just realy pissed that my car ran that slow. I'm def waiting till it gets cold out to run my car again. It's just pointless to tryand get into the 12's when its this damn hot and humid out.

Z

12.7 @ 109
zmanoside is offline  
#4 Old 08-02-2008, 04:03 PM
WRXtuners Member
 
03 CrazyTaxi's Avatar
 
Join Date: Jan 2006
Location: Missouri
Posts: 728
Images: 4
03 CrazyTaxi is known to be trustworthy and helpful 03 CrazyTaxi is known to be trustworthy and helpful
Send a message via MSN to 03 CrazyTaxi Send a message via Yahoo to 03 CrazyTaxi
Yeah humidity and heat FTL. Last night I ran at our Midnight Madness. Wasn't able to check temp or humidity but it was unbelievably hot and humid. At stage 2 on my bugeye, I ran 13.7 earlier this year. After my turbo swap, I should have been running faster. However I could only pull a 14.5. Car was running fine, just couldn't pull off anything better.

VF34'd Corvette Killer aka Doug
03 CrazyTaxi is offline  
#5 Old 08-03-2008, 09:59 AM
WRXtuners Member
 
BC_Girl's Avatar
 
Join Date: Mar 2008
Location: Michigan
Posts: 117
BC_Girl is an unknown
Quote:
Originally Posted by zmanoside View Post
Yeah it sucked pretty bad. I started doing some research myself on the web on drag racing and weather conditions, I found that the barometric pressure has the most effect on racing, followed by temp and then huidity. Hard core bracket racers actually buy "weather stations" small electronic devices that mesure all of these factors and more to determine what their car will run on a specific day in specific weather. I was just realy pissed that my car ran that slow. I'm def waiting till it gets cold out to run my car again. It's just pointless to tryand get into the 12's when its this damn hot and humid out.

Z
Now I'm curious. The barometric pressure is the number one weather condition that affects the way our cars run? What did you find? Is it better if it's high or low?

Boys will be boys, but girls will be fast !
BC_Girl is offline  
#6 Old 09-02-2008, 10:02 PM
WRXtuners Member
 
03 CrazyTaxi's Avatar
 
Join Date: Jan 2006
Location: Missouri
Posts: 728
Images: 4
03 CrazyTaxi is known to be trustworthy and helpful 03 CrazyTaxi is known to be trustworthy and helpful
Send a message via MSN to 03 CrazyTaxi Send a message via Yahoo to 03 CrazyTaxi
Yeah, so I figured it was just the heat and humidity last time... Nope, went to the track this past friday and couldn't run better than 14.4. My tuner tells me my boost is the problem. It's oscillating to the point that it is basically ineffective.

VF34'd Corvette Killer aka Doug
03 CrazyTaxi is offline  
#7 Old 09-10-2008, 06:59 AM
WRXtuners Member
 
Join Date: Sep 2006
Location: Pennsylvania
Posts: 285
Images: 14
Labukas19 is more helpful than not
Quote:
Originally Posted by 03 CrazyTaxi View Post
Yeah, so I figured it was just the heat and humidity last time... Nope, went to the track this past friday and couldn't run better than 14.4. My tuner tells me my boost is the problem. It's oscillating to the point that it is basically ineffective.
well you did .1 better lol

2001 COBRA
Labukas19 is offline  
#8 Old 09-10-2008, 11:54 AM
WRXtuners Member
 
SuBeast's Avatar
 
Join Date: Oct 2007
Location: California
Posts: 731
Images: 3
SuBeast is on thin ice
Garage
Send a message via AIM to SuBeast
^lol... Any improvement is better than none. But my Jetta runs 14.0's maybe 13.9's at it's best... WtF? Definately something up...

You think 90 degrees is heat? ! I live in 100 degree weather daily lol! I think a few weeks ago it hit 110+... Yeah, my car didn't really like that. (omega intake manifold heat-soak.) It's actually cooled down to 89 today and holy moly it's cold! It's supposed to get back into the normal triple digits this weekend though. I need to wait for a cooler day to head back up to the track for some more time's.... Maybe in like October or November it'll get better.

FAST
RELIABLE
CHEAP
Pick 2
2006 STi
1990 Civic time-attack project
1990 Toyota Hilux - daily
SuBeast is offline  
#9 Old 09-10-2008, 02:56 PM
WRXtuners Member
 
zmanoside's Avatar
 
Join Date: Sep 2006
Location: North Carolina
Posts: 430
zmanoside is a helpful contributing member
Quote:
Originally Posted by SuBeast View Post
^lol... Any improvement is better than none. But my Jetta runs 14.0's maybe 13.9's at it's best... WtF? Definately something up...

You think 90 degrees is heat? ! I live in 100 degree weather daily lol! I think a few weeks ago it hit 110+... Yeah, my car didn't really like that. (omega intake manifold heat-soak.) It's actually cooled down to 89 today and holy moly it's cold! It's supposed to get back into the normal triple digits this weekend though. I need to wait for a cooler day to head back up to the track for some more time's.... Maybe in like October or November it'll get better.

You are in cali though...DRY HEAT...come to NC on a hot HUMID day in 100 degree heat with 95% humidity...as letterman says, its the "feels like" temp..ya, feels like 110-115 with the humidity out here..nasty mugginess

12.7 @ 109
zmanoside is offline  
#10 Old 09-10-2008, 03:12 PM
WRXtuners Member
 
BugEyedAWD's Avatar
 
Join Date: Aug 2008
Location: Tennessee
Posts: 92
BugEyedAWD is on thin ice
Send a message via MSN to BugEyedAWD
^ or just go to texas and they will tell you its just plain NOT SAFE to go outside.


but i live at the base of the smokey mountains so if i have heat issues, i just climb altitude. LOL (joke)

but yeah, i dont know what it is, but around here, the temp has sucked. I only pray for winter. the car will run alot better. I notice i use a little bit less fuel when its cooler out too.

:EDIT: ^ if i stay out of boost of course.

Last edited by BugEyedAWD; 09-10-2008 at 03:12 PM. Reason: i suck.
BugEyedAWD is offline  
#11 Old 09-10-2008, 06:03 PM
WRXtuners Member
 
SuBeast's Avatar
 
Join Date: Oct 2007
Location: California
Posts: 731
Images: 3
SuBeast is on thin ice
Garage
Send a message via AIM to SuBeast
It gets humid here too sometimes. It just probably rarer than over where you are. It was pretty humid a couple weeks ago, not sure of the number reading, and it lasted a couple days. But I know waht you mean.

FAST
RELIABLE
CHEAP
Pick 2
2006 STi
1990 Civic time-attack project
1990 Toyota Hilux - daily
SuBeast is offline  
#12 Old 09-16-2008, 11:07 PM
WRXtuners Member
 
headstart101's Avatar
 
Join Date: Dec 2007
Location: California
Posts: 82
Images: 21
headstart101 is an unknown
Quote:
Originally Posted by SuBeast View Post
It gets humid here too sometimes. It just probably rarer than over where you are. It was pretty humid a couple weeks ago, not sure of the number reading, and it lasted a couple days. But I know waht you mean.
I live about 25 minutes away from you, and it gets hot but not humid, mostly dry air. I work on a flight line that would hit about 140 degrees plus at certain times of the day, im talking about the point where your hands are burning literally and your eyes are watering but I guess not everyone here works with FA18 hornets daily. But i cant complain because every year they bring supers cars and bikes to the base to run them on the runway, sometimes against our FA18's , this yea they had bikes like the busa and stuff, but a few years ago they had the bughatti and the hennessee viper and some 911's and a few other million dollar cars, cant wait to see what they bring out next year.
headstart101 is offline  
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On