The 69th Indianapolis 500 was held at the Indianapolis Motor Speedway in Speedway, Indiana on Sunday, May 26, 1985. In one of the most dramatic moments in Indy 500 history, Danny Sullivan took the lead from Mario Andretti on lap 120. But as he was completing the pass, Sullivan's car stepped out, and he lost control. He spun directly in front of Andretti in turn one, doing a complete 360°. Andretti veered to the left and slipped by unscathed, while Sullivan's car somehow avoided contact with the concrete wall. Sullivan continued in the race, and about twenty laps later, managed to re-pass Andretti for good. Sullivan led the final 61 laps, and scored his lone Indy victory, driving for Penske.

Due to the electrifying spin by Sullivan, and the subsequent recovery, the race became known in auto racing lore as the "Spin and Win". It is largely considered one of the most famous moments in all of Indy car racing history.

The race was sanctioned by USAC, and was included as part of the 1985 CART PPG Indy Car World Series. The Speedway also celebrated 40 years of ownership by the Hulman/George family.

The 1985 Indy 500 was the breakout race for the "stock block" Buick V-6 engine. Pancho Carter and Scott Brayton swept the top two spots on the starting grid with the pushrod Buick, setting new track record speeds in time trials. However, both cars still had questionable reliability for the full 500 miles, and both dropped out early with mechanical problems on race day.

Defending champion Rick Mears suffered serious leg injuries in a crash at Sanair Super Speedway in August 1984. He missed the rest of the 1984 season, and would participate only in limited events in 1985. The 1985 Indy 500 was his first race back after recovery.

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