Game Shark Codes: Own The City Part 2 (us):

_C0 One Lap
_M 0x08C376A4 0x00000001
_C0 Two Laps
_M 0x08C376A4 0x00000002
_C0 Three Laps
_M 0x08C376A4 0x00000003
_C0 Nine Laps
_M 0x08C376A4 0x00000009
_C0 Speed Modifier Codes
_M 0xCF000000 0x00000006
_C0 Normal speed
_M 0x08BE444C 0x3C888889
_M 0x08BE4450 0x3DCCCCCD
_C0 Super Slow Motion
_M 0x08BE444C 0x3C888889
_M 0x08BE4450 0x3ACCCCCD
_C0 Slow Motion
_M 0x08BE444C 0x3C888889
_M 0x08BE4450 0x3CCCCCCD
_C0 Quicker Game
_M 0x08BE444C 0x3D088889
_M 0x08BE4450 0x3DCCCCCD
_C0 Hyper Mode
_M 0x08BE444C 0x3D488889
_M 0x08BE4450 0x3DCCCCCD
_C0 Insane Speed
_M 0x08BE444C 0x3D888889
_M 0x08BE4450 0x3DCCCCCD