Top families in the Indy 500

Auto racing has long been something of a family sport – it's common to see two or three generations competing in NASCAR, IndyCar, or the NHRA, among other series. When it comes to the history of the Indianapolis 500, many last names look familiar throughout the years – it's the first names that change over time. Here are a few of the most common names in the history of the Indy 500.

Andretti – the name Andretti has become synonymous with Indy – or, at least, back luck at Indy. Patriarch Mario won the big race only once, in 1969; since then, he and his family have been somewhat curse at Indianapolis Motor Speedway. Four other Andrettis have competed in the race – sons Michael and Jeff, nephew John, and grandson Marco – and three of them (Michael, Jeff and Marco) have followed Mario as Indy 500 Rookie of the year. None of them, however, have been able to join Mario on the Borg-Warner Trophy as winner of the Indy 500.

Foyt – patriarch A.J. has won the "Greatest Spectacle in Racing" four times – the first of three drivers ever to do so. He competed in 35 consecutive Indy 500s, and his team, A.J. Foyt Enterprises, won an additional Indy 500 in 1999. Foyt's adopted son, Larry, competed in three Indy 500s with a best finish of 30th in 2006, while his grandson, A.J. Foyt IV, competed in six Indy 500s with a best finish of 14th in 2007.

Jones – Parnelli Jones won the 1963 Indy 500, but was also known for racing sports cars, stock cars, midget and sprint cars, and off-road vehicles. Son P.J. attempted to qualify for four Indy 500s and competed in two, with a best finish of 19th in 2006.

Mears -Rick Mears was the third driver to win four Indy 500s, and competed against his brother, off-road racing veteran Roger, in five of them. Roger's son Casey attempted to qualify for the 2001 Indy 500, but did not make the race; he later moved on to NASCAR.

Rahal – Bobby Rahal won the 1986 Indy 500, and won the 2004 Indy 500 as a team owner with Buddy Rice as the driver and late-night talk show host David Letterman as co-owner. Son Graham found success as a 19-year-old, winning the first IndyCar Series race he competed in. After running part-time in 2010, the younger Rahal is part of Chip Ganassi Racing in 2011.

Unser – the only family to have three Indy 500-winning members, Al Unser Sr., his brother Bobby and son Al Jr. have nine race wins between then: Al Sr. with four, Bobby with three, and Al Jr. with two. Those aren't the only Unsers to race at Indy, however: Al and Bobby's brother Jerry, Bobby's son Robby, and Jerry's son Johnny have also competed in the Brickyard's biggest race. Yahoo Sports