The Penske PC-23 was a highly successful CART racing car that competed in the 1994 IndyCar season with Penske Racing, and in 1995 IndyCar season with Bettenhausen Motorsports. It was designed by Nigel Bennett, who based its design on the 1993 car, the PC-22, which was a radical departure from the basic concept of the previous Penske cars. The PC-23 was one of the most dominant open wheel race cars ever developed. It won both the 1994 CART season, and the 1994 Indianapolis 500 with Al Unser Jr., together with Emerson Fittipaldi and Paul Tracy scoring 12 wins out of 16 in total, collecting 10 pole positions and 28 podium finishes, in a season that saw Penske also take the Constructor's Cup, and the Manufacturer's Cup with the Ilmor-Mercedes-Benz engine. Nevertheless, the car is mostly known for the controversial pushrod Mercedes-Benz 500I engine, designed and developed for the single race of Indianapolis, exploiting a loophole in different technical rules between the Indy 500 and CART sanctioning bodies at that time.

The PC-23 was a design evolution of its predecessor, the PC-22, which won the 1993 Indianapolis 500, 8 races over the entire season, and missing the 1993 CART title by only 8 points. The only substantial difference of the new car from it were the smaller rear wings on the short ovals, mandatory by rule changes for the 1994 season, and Team Penske put in a lot of test efforts to minimize the effects of these changes. There were also some modifications on the transmission, but the new car was mostly an progression. Plans to fit the PC-23 with an active suspension system were canceled due to a ban by CART on such technology. The car and the Ilmor engine were ready for testing by mid December 1993.

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