The 1991 CART PPG Indy Car World Series season was the 13th national championship season of American open wheel racing sanctioned by CART. The season consisted of 17 races, and one non-points exhibition event. Michael Andretti was the national champion, and the rookie of the year was his younger brother Jeff Andretti.
The 1991 Indianapolis 500 was sanctioned by USAC, but counted towards the CART points championship. Rick Mears won the Indy 500, his record-tying fourth victory in the event.
Michael Andretti won a total of eight races, eight pole positions, and led more than half of the laps during the season, but the championship battle still went down to the final race of the season. Bobby Rahal won only one race, but had 11 podium finishes and 13 top tens. Rahal's consistent season put him in position to challenge Andretti for the title in the season finale at Laguna Seca. Andretti got off to a slow start to the season, dropping out of the first two races, and finished a heartbreaking second at Indianapolis. But after Indy, he shot to the top of the standings. He won four of the last five races of the season, and needed to finish 6th or better at Laguna Seca to clinch the title. When Bobby Rahal dropped out at Laguna Seca with overheating problems, Andretti cruised to the title.
Drivers and constructors The following teams and drivers competed for the 1991 Indy Car World Series. All entrants used Goodyear tires.
TeamChassisEngineNo.Driver(s)StatusRound(s)Ref(s)Arciero RacingPenske PC-17Buick12 Mark Dismore1–4Lola T89/00 Pancho Carter4–5 Jeff Wood6–7 John Jones8–17A. J. Foyt EnterprisesLola T91/00Chevrolet14 Bernard Jourdain2 Al Unser3 A. J. Foyt4–9, 11, 16 Mike Groff10, 12, 14–15, 17Lola T90/00Buick48 Bernard Jourdain4Bayside MotorsportsLola T91/00Cosworth86 Jeff AndrettiAllBettenhausen MotorsportsPenske PC-19Chevrolet16 Tony Bettenhausen Jr.AllChip Ganassi RacingLola T91/00Chevrolet8 Eddie CheeverAllDale Coyne RacingNu-Tech RacingHemelgarn Coyne RacingDale Coyne / BettenhausenLola T90/00Cosworth19 Randy Lewis1–4, 9–12, 14–15, 17 Dale Coyne5, 7 Buddy Lazier8 Ross Bentley13 Dennis Vitolo16Lola T89/00391, 6Lola T90/00 Paul Tracy2 Jeff Wood3 Buddy Lazier10, 12, 17 Michael Greenfield14–15Lola T88/0090 Buddy Lazier1Lola T90/006, 15Lola T89/00 Dennis Vitolo2Penske PC-19Chevrolet Cor Euser17D. B. Mann MotorsportsLola T90/00Buick93 John Paul Jr.4Dick Simon RacingLola T90/00Lola T91/00Cosworth7 Hiro Matsushita1–3, 5–16Buick4Chevrolet1722 Scott BraytonAllParagon MotorsportsCosworth23 Tero Palmroth4Euromotorsport RacingLola T90/00Cosworth Franco Scapini1 Didier Theys4 Tony de Tommaso12 Nicola Marozzo13–1550 Mike Groff1–3Lola T91/004–9Lola T90/00 Roberto Guerrero10Lola T91/00 Jeff Wood12–17Galles-Kraco RacingLola T91/00Chevrolet Al Unser Jr.All18 Bobby RahalAllGenoa RacingLola T90/00Cosworth Guido Daccò2–4, 6–7Hall-VDS RacingLola T91/00Chevrolet4 John AndrettiAllHemelgarn RacingLola T90/00Buick71 Buddy Lazier492 Gordon Johncock4Hemelgarn-Byrd RacingLola T91/0091 Stan Fox4Kent Baker RacingLola T89/00Buick97 Dean Hall4King MotorsportsLola T91/00Buick26 Jim Crawford4 Roberto Guerrero6, 12, 17Leader Card RacingLola T90/00Cosworth Dean Hall1 Didier Theys2, 6–10, 12, 14–15, 17 Pancho Carter4, 11 Johnny Parsons4–5Menard RacingLola T91/00Buick9 Kevin Cogan451 Gary Bettenhausen4Lola T89/0059 Tom Sneva4Newman/Haas RacingLola T91/00Chevrolet Michael AndrettiAll6 Mario AndrettiAllPatrick RacingLola T91/00Alfa Romeo20 Danny SullivanAll40 Roberto Guerrero4Penske RacingPenske PC-20Chevrolet3 Rick MearsAll5 Emerson FittipaldiAllPenske PC-1917 Paul Tracy11, 16–17P.I.G. EntreprisesLola T89/00Judd31 Ted Prappas1–2, 4Lola T91/006–10, 12–15, 17Thom Burns RacingLola T89/00Judd66 Dominic Dobson4Todd Walther RacingLola T89/00Cosworth44 Phil Krueger1–2 Buddy Lazier2TruesportsTruesports 91CJudd Scott PruettAll21 Geoff Brabham4UNO RacingLola T91/00Judd15 Scott GoodyearAllVince Granatelli RacingLola T91/00Chevrolet Arie LuyendykAllWalker MotorsportLola T90/00Buick10 Willy T. Ribbs4Cosworth6, 8–9, 12–13, 15–17 Jon Beekhuis11 Buddy Lazier14Walther MotorsportsPenske PC-18Cosworth77 Salt Walther4
Driver changes
Preseason On August 6, 1990, Bettenhausen Motorsports confirmed its plans for a full 1991 campaign with driver/owner Tony Bettenhausen Jr. in the No. 16 car. On September 18, 1990, Penske Racing announced it would downsize its program back to a two-car team for 1991 by not exercising their option on Danny Sullivan, as sponsorship from Pennzoil had switched to Hall/VDS Racing. On October 8, 1990, Hall/VDS Racing announced it had signed John Andretti as their lone driver in a two-year deal. Andretti switched to the No. 4 car from Porsche North America after the German manufacturer stopped its Indy Car program. On October 12, 1990, King Motorsports announced the signing of Jim Crawford for its partial schedule in the No. 26 car, including the Indianapolis 500. On October 30, 1990, Patrick Racing announced that Danny Sullivan had signed to drive the No. 20 car in 1991, replacing Roberto Guerrero. On November 3, 1990, Bayside Racing signed Jeff Andretti as its new driver for the No. 86 car, replacing Dominic Dobson. On November 20, 1990, A. J. Foyt announced his plans to retire from competition after the 1991 season, during his recovery from the leg and feet injuries sustained on September 23, 1990, in a crash at Road America. Foyt, who had dismissed the notion of retirement in early press conferences after his crash, clarified it had been his plan all along. However, he remained non-committal for the rest of 1991 regarding his future plans. On December 14, 1990, Scott Pruett received the mandatory medical approval to return to the No. 11 Truesports car for 1991. Pruett had been sidelined for the whole 1990 season due to severe leg injuries in a pre-season crash, with Raul Boesel as the fill-in driver throughout the year. On January 8, 1991, Menard Racing announced that Kevin Cogan and Gary Bettenhausen would drive its two Buick-powered Lola T91/00 cars at the Indianapolis 500, entered as No. 9 and No. 51. Bettenhausen had driven a year-old Lola with Menard in the previous edition. On February 8, 1991, the Indianapolis News reported that Euromotorsport had signed John Jones to drive the No. 50 car, taking the place of Mike Groff. However, the necessary funding for the seat did not materialize, and Jones was replaced for the Surfers Paradise round by the returning Groff, who would remain in the car as the full-time driver. On January 30, 1991, Arciero Racing announced the signing of rookie Mark Dismore, who replaced Randy Lewis in the No. 12 car. Dismore was the reigning champion of the Atlantic Championship in the discontinued Pacific Division, and had made one previous Indy Car start in 1989. In February 1991, Dale Coyne Racing signed Randy Lewis to drive the No. 19 car in 1991, replacing Dean Hall. On February 5, 1991, P.I.G. Enterprises announced that rookie Ted Prappas would drive the No. 31 car, replacing Jon Beekhuis. Prappas had finished second in the American Racing Series standings with one win, behind series champion Paul Tracy. Due to the team's low budget for the season, Prappas skipped all oval races except for the Indianapolis 500, where he failed to qualify after crashing twice. Subsequently, his equipment was upgraded from a Lola T89/00 to a T91/00. On February 8, 1991, Dick Simon Racing announced that Hiro Matsushita would be the full-time driver of the No. 7 car, after a partial schedule in his debut season. Matsushita's car was powered by a Cosworth engine, except for his first serious attempt at the Indianapolis 500, which was planned with a Buick stock-block. For the final race of the season at Laguna Seca, Matsushita drove a Chevrolet engine, in anticipation of his supplier switch for 1992. On February 14, 1991, Hemelgarn Racing announced the signing of Stan Fox in the No. 91 car for the Indianapolis 500, as part of a new partnership with Jonathan Byrd Racing. Fox was tasked with a Lola T91/00 chassis, the first brand-new car of his Indy Car career. Both team owners had lost their Indy 500 drivers over the previous year, after Rich Vogler and Billy Vukovich III were both killed in separate sprint car races; Vukovich had been due to sign for the joint venture at the time of his death. On February 16, 1991, A. J. Foyt Enterprises announced that the team would skip the opening race of the season at Surfers Paradise, and that Bernard Jourdain would drive the No. 14 car at Long Beach in place of the injured A. J. Foyt, who aimed to return at Phoenix. This marked Jourdain's own return since rupturing his spleen in a practice crash at Indianapolis in 1990. On February 19, 1991, Dale Coyne Racing announced it had signed the reigning American Racing Series champion Paul Tracy to drive for the team for an undetermined number of races, starting at Long Beach in the No. 39 car. Tracy had previously signed a three-month testing deal with Truesports in October 1990 that failed to evolve into a ride due to a lack of sponsorship. On February 27, 1991, Todd Walther Racing announced that Phil Krueger would drive the No. 44 car full-time from Long Beach onwards, replacing Jeff Wood. However, he was later entered for the Surfers Paradise season opener as well. On March 4, 1991, Genoa Racing announced that Guido Daccò would drive the No. 33 full-time from Long Beach onwards. On March 13, 1991, A. J. Foyt Enterprises entered Bernard Jourdain for the Indianapolis 500 as the driver of the No. 48 car. Jourdain drove a Buickengine, the first and only time in history that a Foyt car carried such powerplant in Indy car racing. The following drivers were entered for the Surfers Paradise race and other events without a prior announcement Euromotorsport Racing entered rookie Franco Scapini in the No. 42 car. Scapini was a former International Formula 3000 driver that served as a Formula 1 test driver for the Life F1 team in 1990, and had one previous start in the American Racing Series in 1988. He was featured in The Indianapolis Star as a full-time entrant, and was entered for the events at Long Beach and Phoenix, but failed to appear at either race, and the Indianapolis News reported on April 23 that he had been demoted due to non-payments from his sponsors. In a 2025 interview, Scapini claimed that a steep asking price from Euromotorsport prevented him from continuing. Dale Coyne Racing entered Buddy Lazier in the No. 90 car, with an older Lola T88/00 chassis, and Dennis Vitolo in the car serviced by Nu-Tech Motorsports. Vitolo, who had raced once in 1988 and failed to qualify for two events in 1989, also started under this arrangement at Long Beach and Detroit. Leader Card Motorsports signed one-race deals with Dean Hall and Didier Theys to drive the No. 21 car at Surfers Paradise and Long Beach, respectively. The team later sat out Phoenix in order to preserve its lone chassis for the Indianapolis 500.
Mid-season During March and April, a number of drivers were entered for the Indianapolis 500 without a prior announcement On March 21, 1991, Truesports entered Geoff Brabham in the No. 21 car for the Indianapolis 500, also rekindling the association from the 1990 edition. On March 27, 1991, Genoa Racing entered Vinicio Salmi in a second car for the Indianapolis 500. However, Salmi never turned a wheel in rookie orientation or official practice, due to Genoa's economic issues. On April 2, 1991, Hemelgarn Racing entered Buddy Lazier in the No. 71 car for a second attempt at his first Indianapolis 500, driving a newly rebuilt Lola T90/00. On April 3, 1991, Walther Motorsports entered Salt Walther as the driver of the No. 77 car, again in a two-year-old Penske model.