There's a good layman's definition plus plenty more info at www.autocross.com The autocross rulebook unfortunately contains a laughably complex and nitpicky set of allowble mods between classes.
Pacific Green '96 Contour LX V6, loaded
'98 Grand Prix GTP 14.88/91 bone stock, awaiting new times from 3.4 pulley, CAI, U-bend removal but it's creeping up on the...
Calypso Green '92 Mustang LX coupe, 13.56/101
3-time local class champion autocrosser
Racing school whore
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