Brian Beckman's The Physics of Racing
The how's, why's and wherefore's of punting a car around a track... the entire Physics of Racing Series (PhoRS) by Brian Beckman, PhD
http://www.miata.net/sport/Physics/
(A big thanks to Robertp for contributing this link containing some valuable info. It looks so good I added it to the Racecraft section as well. Thx Robert and way to go mate!)