Yahoo Sports reports: NASCAR has produced legends over its seven-plus decades of competition — men who defined what it means to win on superspeedways, short tracks, and road courses. While ranking the all-time greats is always a heated debate among fans, certain names rise above the rest based on championships, wins, and impact on the sport. Here's our take on the 10 greatest drivers in NASCAR history. 1. Richard Petty — "The King" No conversation about NASCAR greatness begins anywhere but with Richard Petty. With 20