Indy 500 and USAC racing 1975
AJ Foyt took further advantage of USAC's boost rules in 1975 and his Coyote, the sole car powered by the Ford-designed quad cam engine, dominated the season.
McLaren built a further evolution of their M16 series, the M16E being driven by Johnny Rutherford to second place in the title race - again - but no new Eagles were built for 1975 and this started a rethink in many team owners' minds about building their own cars. Lindsey Hopkins had already built his own car in 1974, another Bob Riley design on similar lines to the Coyote, but the Silver Floss Sauerkraut Special did not prove competitive. Despite this, George Bignotti at Patrick Racing asked Riley to build a third Indy design, to be known as the Wildcat Mk I, for regular drivers Gordon Johncock and Wally Dallenbach. It was equipped with the new Bignotti-inspired DGS engine, an evolution of the ancient Offy turbo. Parnelli had moved up to Formula 1 but were running a 1974 Eagle for Al Unser and also exploring their own new engine, a turbo-charged version of the Formula 1 Cosworth DFV. Unser gave this engine its debut in the back of a new Parnelli VPJ6 before the end of the season.
Also running competitive cars in 1975 were Penske (Norton Spirit McLarens), AAR (Jorgensen Steel Eagles), Jerry O'Connell (Sugaripe Prune Eagles) and Bob Fletcher (Cobre Tire Eagles); all using 1974 cars.
02 Mar 1975 > California 500 Qualification Heat 1 at Ontario Motor Speedway
02 Mar 1975 > California 500 Qualification Heat 2 at Ontario Motor Speedway
09 Mar 1975 > California 500 at Ontario Motor Speedway
16 Mar 1975 > Phoenix 150 at Phoenix International Raceway
06 Apr 1975 > Trenton 200 at Trenton International Speedway
25 May 1975 > Indianapolis 500 at Indianapolis Motor Speedway
08 Jun 1975 > Milwaukee 150 at Milwaukee (Wisconsin State Fair Park)
29 Jun 1975 > Pocono 500 at Pocono International Raceway
20 Jul 1975 > Michigan 200 at Michigan International Speedway
17 Aug 1975 > Milwaukee 200 at Milwaukee (Wisconsin State Fair Park)
13 Sep 1975 > Michigan 150 at Michigan International Speedway
21 Sep 1975 > Trenton 150 at Trenton International Speedway
09 Nov 1975 > Phoenix 150 at Phoenix International Raceway
1975 USAC National Championship table
|1||AJ Foyt||Coyote 74 - Foyt turbo|
Coyote 75 - Foyt turbo
|4920 pts||7 wins|
|2||Johnny Rutherford||McLaren M16E - Offy 159 ci turbo||2900 pts||1 win|
|3||Bobby Unser||Eagle 74 - Offy 159 ci turbo||2480 pts||1 win|
|4||Wally Dallenbach||Eagle 74 - Offy 159 ci turbo|
Wildcat Mk 1 - DGS 158ci turbo
|2305 pts||1 win|
|5||Billy Vukovich||Eagle 74 - Offy 159 ci turbo||2080 pts||0 wins|
Points table by Phil Harms.