Ilmor-Chevrolet 265-A engine
The Ilmor 265-A is a turbocharged,, V-8 Indy car racing engine, designed and developed by Ilmor, for use in the CART PPG Indy Car World Series; between 1986 and 1993.
History
Mario Illien and Paul Morgan were working at Cosworth on the Cosworth DFX turbocharged methanol engine for the CART Indy Car Series; differences of opinion over the direction in which DFX development should go led them to break away from their parent company to pursue their own ideas. There was some acrimony in their split from Cosworth, their former employer claiming that the Ilmor engine was little different from their planned modifications to the DFX.1986
Founded as an independent British engine manufacturer in 1983, Ilmor started building engines for Indy cars with financial backing from team owner and chassis manufacturer Roger Penske. The Ilmor 265-A, badged initially as the Ilmor-Chevy Indy V-8, debuted in [1986 Championship Auto Racing Teams|CART PPG Indy Car World Series|1986]. The engine was used part-time by Penske team drivers, with Al Unser Sr. racing it at the 1986 Indianapolis 500. Mears notched two poles and two 3rd place finishes with the engine late in the season.1987–1991
In 1987, the 265-A engine program expanded to full time at Penske Racing. Penske's primary drivers Rick Mears and Danny Sullivan raced it full-time. A third car was entered at Indianapolis for Danny Ongais. However, Ongais was injured in a crash during practice. He was replaced by Al Unser Sr.. The 265-A was also fielded by Newman/Haas Racing and at Patrick Racing. Andretti won at Long Beach, the engine's first Indy car victory. He also won the pole position for the 1987 Indianapolis 500.With the 265-A engine now badged as the Chevrolet Indy V-8, Rick Mears won the 1988 Indianapolis 500, the engine's first win at Indianapolis. The engine went on to have a stellar record in CART. From 1987 to 1991, the "Chevy-A" engine won 64 of 78 races including the Indy 500 from 1988 to 1991.
1992
In 1992, the 265-B engine was introduced. The "Chevy-B" was fielded singly by Penske Racing in 1992 and won four CART series races. All other Ilmor teams remained with the venerable 265-A for 1992. Bobby Rahal, driving a "Chevy-A" won the 1992 CART championship, the fifth consecutive for the 265-A. Al Unser Jr. won the 1992 Indianapolis 500 driving a "Chevy-A", also the fifth consecutive Indy 500 win for the 265-A. Emerson Fittipaldi drove a "Chevy-B" to 4th place in points, but both he and Mears dropped out of that year's Indy 500 due to crashes.At this time Ilmor faced new competition from Cosworth, which had just introduced their new Ford-Cosworth XB V-8.
1993–1994
For the 1993 season, the 265-C engine was introduced as a replacement for both the 265-A and the 265-B. The "Chevy-C" was used widely, and brought continued success for Ilmor. Some backmarker teams continued to run 265-A or 265-B engines during the 1993 season, but neither the "A" nor the "B" would win another Indy car race. Chevrolet dropped its badging support after the 1993 season.In 1994, Ilmor introduced two new engines, the 265-D and the 265-E. The "D" would later be badged as the "Ilmor Mercedes-Benz D". The "E" was a top-secret purpose-built, V-8 pushrod engine developed for Team Penske for the 1994 Indianapolis 500. While most Ilmor teams upgraded to the "D", the "C" and a variant called the "C+" saw some limited use during the 1994 season.