Truesports 91C Steve Horne, the president of Truesports, commissioned the project in 1989 to develop the first "Made in America" Indy car since the
1986 Eagle, with a design team led by chief engineer Don Halliday and aerodynamicist Gary Grossenbacher. The Truesports 91C was built in
Hilliard, Ohio, and the
Ohio State University allowed the team to open a wind tunnel formerly used by the
U.S. Air Force at
Port Columbus, six miles from the Truesports team's workshop. The 91C was designed around its driver,
Scott Pruett, The 92C featured a higher nose and Corsair wing, resembling those on Formula One cars of the era. The 92C showed potential during the early season, with Pruett finished 7th at Phoenix and qualifying 3rd at Long Beach. However, following Horne's departure from the team in June 1992, the team announced that it would be disbanded following the season and ceased development of the chassis. Halliday and Grossenbacher also joined the Rahal-Hogan team to continue development of the 92C chassis. suffering a crash in the process. The chassis would also be tested at
Laguna Seca during the winter, with reportedly optimistic results. Rahal struggled further at Phoenix, retiring from the race with handling problems. However, the chassis showed competitiveness at the
Long Beach street circuit, where Rahal achieved the chassis' best-ever finish with a 2nd place finish. During April, newly appointed test driver
Mike Groff tested the R/H-001 at Indianapolis, achieving a top lap of 217.9 mph on April 23, but noted that the car struggled in the turns. Groff, who was originally slated to begin his racing season after the Indianapolis 500, nonetheless appeared in official practice during the month of May, sharing the R/H-001 with Rahal. Both R/H-001 cars struggled to get up to speed during practice, and Rahal waved off his first qualification attempt on May 15 after a lap of 214.179 mph. On the second qualifying day, Rahal qualified with a 4-lap average of 217.140 mph; however, he noted that the car seemed to be "extremely sensitive to the weather, and the hotter it gets, the worse it handles." Rahal's car stayed in the field until 15 minutes prior to the end of Bump Day qualifying, when
Eddie Cheever bumped Rahal with a qualifying speed of 217.599 mph. Rahal subsequently attempted to qualify his spare car in the final moments of Bump Day, but came up short with an average of 216.342 mph. Rahal originally intended to introduce an all-new design, the R/H-002, in June; however, this project was cancelled following the team's failure to qualify for the 1993 Indianapolis 500. After Indianapolis, Rahal switched to the more conventional Lola chassis, while Groff entered selected races in a Miller Genuine Draft Light-liveried R/H-001, scoring points in 3 races and leading a lap at Milwaukee. == Complete Indy Car World Series results ==