Get All Tracks And All Vehicles
First hook up two controllers. Press Start on controller 1 until you see the screen that says "Push Start" then on controller 2 press Up on the + Pad (not control stick), Down C, R, L, and Z all at once. Then let go of all buttons and immediately press Start or the A button on controller 1 to enter the Grand Prix mode. Then you should have every track and vehicle. Turbo Start
At the starting line hold A and B. Just as the announcer says GO let go of the B button only for a turbo start.

Get The China Town Jam Track
In Grand Prix mode with the Expert difficulty get first place on each course, and you will have the China Town Jam Track.

Get The Neo Speed Way Track
In Grand Prix mode with the Intermediate difficulty get first place on each course, and you will have the Neo Speed Way Track.

Drive With The N64 Controller
In Time Attack mode get a race time that ends in .064 seconds.

Get The Dominator
Defeat the game in first place in the Expert difficulty using the Black Lighting.

Get The Prowler
Defeat the game in first place in the Expert difficulty using the Hornet.

Get The Reaper
Defeat the game in first place in the Expert difficulty using the Shredder.

Get The Vengeance
Defeat the game in first place in the Expert difficulty using the Avenger.

Turbo Boost While Racing
While holding down the A button make a hard left or a hard right holding the Z button, then let go of both the A and Z buttons right after you let go start tapping the A button and you will get a turbo boost.