Link to free air density tuning info for drag racing at NHRA drag racing:
AAA Insurance NHRA Midwest Nationals, Sep 27-29,
World Wide Technology Raceway, (formerly Gateway International), Madison, IL, (618) 215-8888;
Map location, air density, density altitude, grains, forecast, historic, & metric data "for good spark plug readings":
https://airdensityonline.com/track-r...orsports_Park/