Weather and performance
 

How much ET change do you guys see based on weather ( using the same track ) from the best air to the worst?
Using the quarter mile.
I'd like to know if a tenth (or so) is average , from one end of the "spectrum" to the other.

Re: Weather and performance
 

good bracket door cars on gas here in the NE will swing 3 tenths, 3 MPH and .05 in 60 foot from best to worse over a season at the same track with no tuning changes.

Re: Weather and performance
 

Thanks Ed
I saw a 2.5 MPH swing from April in just the eighth! About a MPH in the quarter.......same pass..I lost a tenth in the eighth and about .15 over the quarter. I may have something else going on......springs , clutch......not sure yet.

Re: Weather and performance
 

stick cars ain't my thing but If I can be of further help just ask here or email.

Re: Weather and performance
 

Thanks

Re: Weather and performance
 

I would say .30-.35 here in the midwest.

Re: Weather and performance
 

Having a weather station is crucial. Not only for ET prediction but to tell wether or not changes you make to the vehicle are positive or negative and weather is not skewing your results. It will also help with determining if your having me handicap issues.

Re: Weather and performance
 

A tenth would not be unusual. a 1500 ft. of air change will move most gas cars a tenth. It's like a 20 degree temp change, a big moisture change or a big pressure change would have a similiar effect. On a race weekend it would be unusual to see a tenth change but from March to June in Louisiana would be a tenth or more of change. Going from 50 degree or so to 80,90, 100 degrees with the resulting moisture and pressure change could move a car 2 or three tenths. Dallas this year was very good air, close to zero or low hundreds. When the temps heat up the air density will rise to 3 or 4 thousand resulting in three tenths of et change.

Re: Weather and performance
 

Thanks for the replies!

Re: Weather and performance
 

This is the site I use * http://www.dragtimes.com/da-density-...e=Calculate+DA * I spent some time there and made up a sheet I refer to. ---Trevor