[Richard Grant]

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.