Indy 500 and USAC racing (1971-1978)
A new era of US motor racing began in 1971 with the separation of the USAC championship into separate divisions for dirt racing, road courses and paved ovals. This section follows the highly successful oval racing series through to the arrival of the CART series in 1979.
This eight-year, 110-race period spans from the 1971 McLaren M16 and "Johnny Lightning 500" Lola T150-based Bignotti Colt-Offy to the 1978 Penske PC6-Cosworth DFX but is more than anything the era of the classic 1972 Eagle Model 5. The period saw 29 Eagle victories, 26 for McLaren, 19 for AJ Foyt's irrepressible Coyotes, 15 for Parnelli, eight for the Patrick Racing Wildcats and three for Chaparral Racing's 1978 Lola T500.
Numerically, Eagle dominate this period with 37% of all entries, followed by McLaren on 15% and then Wildcat leading the rest on just 5%. Only four other constructors average more than one entry per race: AJ Foyt's ever-present Coyotes, Grant King's creations and late-comers Parnelli and Lightning. Of the designers, Bob Riley is well-represented with the 1973 Coyote design, the 1974 'Riley' and the 1975 Wildcat; Roman Slobodynskyj designed the classic 1972 Eagle and the 1976 Lightning.