Mark Dismore is a former driver in the Indy Racing League and the 1990 Toyota Pacific champion as well as the winner of the 1993 24 Hours of Daytona with Dan Gurney's All American Racers in a Toyota GTP car with co-drivers Rocky Moran and P. J. Jones. He made 3 CART starts in 1991 but was badly injured in a practice crash for the Indianapolis 500, when his car veered sharply towards the entrance of pit road at the exit of Turn 4 and back-ended the fence, only to careen across the pit lane and smash virtually head on at sizeable speed against the edge of pit wall; this second impact tore off the front of the car leaving Mark's legs exposed. Amongst the injuries he suffered, the most severe was a broken neck. He was largely out of open wheel racing until the 1996 Indy 500 where he drove for Team Menard though he did try to qualify in the 1992 Indianapolis 500 for Concept Motorsports in an outdated Lola/Buick. In 1997 he drove a second car at the Indy 500 for Kelley Racing and would become a full-time fixture there until the 2001 season. He returned to Menard for a partial season in 2002. Dismore has a single IRL win coming in the fall 1999 Texas Motor Speedway race and also finished a career-best third in points that season. Among his 62 career IRL starts he won four poles. He also represented the IRL in the International Race of Champions in 2000 and 2001.

Greenfield is a city in and the county seat of Hancock County, Indiana, United States It lies in Center Township and is part of the Indianapolis metropolitan area. The population was 23,488 at the 2020 census.