Completed Circuit Code
For most US versions, enter:
8DP5KG5L4G59P
G92WVCQY0DRDQ

For Japanese and a rare few US versions, enter:
9DQ6LH6M5H6$Q
H$3XWCR01DTDR

Resurrect in Place No Game Timer
At the Setup screen, press and hold Z, C-Down and C-Up. Let go. Then press and hold C-Up and C-Down.

Drive the Burning Wreck
At the Car Selection screen, hold C-up and press Z four times.

Fly Up
Turn on Resurrect in Place and Auto-Abort Disable. Now, hit the Resurrect Key and then immediately hold the brake. When your car stops blinking, repeat.

Play tag
Start a two-player practice game. During the countdown, player 1 must hit C-Up (abort button). The second player will be it. Whoever is it when time runs up loses.

Drive the Formula 1 Car
Beat all 24 races in Circuit Mode. Go to the Track Select screen and press Z four times. A horn should sound if done correctly. Note: You can't have all three cars selected at once.

Secret Tunnel
On level 2, drive through the course until you come to the free-way overpass that can be jumped. Instead of jumping down to the road beneath, angle the car so that it is going from right to left. If you go off just right you'll fly across the gap to the other side of the freeway where a secret loop and two keys await.

Secret Stunt Track
In track 6, follow the pathway which passes a white citadel (at top of the mountain) and then leads into the dirt path. The stunt track is located over the mountain's cliff facing away from the citadel. It's at the bottom of the mountain right next to the ocean, so be careful!

Auto-abort Disable
At the Setup Screen, tap C-Up four times quickly. You won't be picked up and set back on the track anymore!

Change Back Tire Size
At the Car Select screen, press: C-Right, C-Left, C-Left, C-Right.

Change Front Tire Size
At the Car Select screen, press: C-Left, C-Right, C-Right, C-Left.

Change Gravity
At the Setup screen, hold Z and press UP, Down. Let go of Z and press Up, Down, Up, and Down.

Change Viewing Distance
While racing, hold L and press down on the control stick.

Cycle the Random High Score Names
At the Fast Times or Best Laps screens, press: L, R, L, R, L, R, L, R.

Disable Car Collisions
At the Setup screen, press Left, Right-(C-Right), C-Up, C-Left, C-Down, Z.

Foggy Night
While playing, hold down all 4 C-buttons and select "extreme fog."

Change Fog Color
At the car select screen, hold Z and press C-Down, C-Down, C-Down.

Turn Car into a Mine
At the Car Select screen, press C-Right, C-Right, Z, C-Down, C-Up, Z, C-Left, C-Left. All cones will show up as mines as well.

You can play the Alcatraz level on San Fransisco Rush! Im not kidding, cause I have done it. This is how you do it:
First go to circuit, then enter the winning circuit code (N64 C&C already has it posted) then after you enter the code, select continue circuit. When the race starts, just drive around and let the time run out. It will say game over, then it will give you a trophy for winning the race, (cause you entered the code) after they give you the trophy, wait for it it tip over, dont press any buttons until then! When it does tip over, press start, then press the B button to go to the main screen (The one with Race, Practice, Circuit, etc.) Then do as follows:
NOTE: you should only use the A and B buttons now to shift through the screens, dont use start.
1.) Go to the normal race, and keep pressig the A button until you get to the car select screen, then, once there press and hold C-Left, then press and hold Z, release both buttons, and press down on the analog stick.
2.) Now go to the setup screen. Hold C-Up, then hold Z, release both buttons and press up.
3.)Go to the track select screen and Hold C-right, then hold Z release both and press right.
4.) Now, go to the car select screen and hold C-Down, then hold Z release both then press down then L , then R. If you did it correctly, a woosh sound will occur, then go to the track selection screen, and there will be a track 7, Alcatraz.