Extra menu item:
Press [Circle, X, Triangle, Square] three times at the title screen.

Drag race:
For one player mode, highlight the "Qualify" option on the Indy 500 mode screen and hold L1 + L2 + R1 + R2 + Start. For two player mode, hold L1 + L2 + R1 + R2 + Start at the handicap screen.

Alternate replay views:
Hold Select and press L1, L2, R1, R2, Triangle, Square, or X during the replay