Use a memory card with a saved game from Burnout with free mode unlocked. Start Burnout 2 and load that game.
Unlock any cheat and the "Cheat Mode" selection will appear at the options screen. Note: Races will not be counted as wins with any cheat activated.
Successfully complete all Grand Prix Championships with gold medals to unlock the "Invulnerability" option at the "Cheat Mode" menu.
Successfully complete Crash mode with all gold medals on all fifteen tracks to unlock the "Runaway" option at the "Cheat Mode" menu. This is a free-play type Crash mode with no goals or brakes. Note: Hold R to boost at the start.
Successfully complete the Custom Series Championship to unlock the "Freerun" option at the "Cheat Mode" menu.
Win all the face offs in the first championship.
Successfully complete Pursuit 3 to unlock two player pursuit mode.
Successfully complete the first set of Offensive Driving 101 lessons to unlock multi-player mode.
Unlock everything in the Custom Series Championship to unlock the "Unlimited Boost" option at the "Cheat Mode" menu.
Get all gold medals in every race and win everything in the first championship to unlock the Custom Series Championship. There will be about six more cars that you can unlock.
Complete the Custom championship two times and get best score possible in the races to unlock the 1997 Eclipse and 2001 Focus SVT.
Win the Custom Series Qualifier to unlock the Custom Compact car.
Win all gold medals at the Split Second Grand Prix to unlock the Custom Coupe car.
Win Pursuit 6 to unlock the Custom Muscle car.
Win Pursuit 5 to unlock the Custom Pickup truck.
Win all gold medals at Point Of Impact Grand Prix to unlock the Custom Roadster.
Win all gold medals at the Speed Streak Grand Prix to unlock the Custom Sport car.
Win Pursuit 4 to unlock the Custom SUV.
Win Pursuit 2 by destroying the classic 1970 car with the police car. This car has average to bad stats, but it can get past a police car very quickly in Pursuit mode and in races.
Complete Driving 101 with all gold medals to unlock the Drivers Ed car.
Win Pursuit 3 to unlock the Gangster car.
Win Face Off 1 to unlock the Hot Rod car.
Win Face Off 3 to unlock the Japanese Muscle car.
Race Face-Off 2 against the Oval Racer. The race is five laps around Airport Terminal 3 (one of the first races). If you manage to defeat it, you will unlock it. This car has great acceleration, maximum control, and maximum top speed.
Win Pursuit 1 by destroying the criminal's car before it gets away to unlock the police car. The police car has maximum top speed, average control, and good acceleration.
Win Face Off 4 to unlock the Super Car.
When you unlock any of the cheats, they normally cannot be used to win championship mode. However, there is a way around this. Simply use the cheat to come in first until the last race. Then, go to the main menu and disable the cheat. You will have all the medals, and all you have to do is win the last race.
At the countdown, when the view is at the back of your car, hold A. Then, tap B while holding A and smoke should start coming out of your tires. Keep holding A. A split second before "GO!" appears, release A and immediately press it again. This should give you a boost.
If you are not at the pole position, try to drive into the rear end of an opponent. He will lose control for a moment and you can pass. Also, never follow the opponents in front of you. Almost always, there is a faster route even if it is takes sharper bends.
When doing the tire burn, once you go around the turn and have a boost, press R. You will speed up and take the turn very fast. Also, if you get a perfect lap you will automatically get a boost.
You can get a boost easier by doing drifts. However press B, drift, then keep tapping B for a better chance of not crashing. Also, drive on the wrong side of the road to receive a boost faster. If your opponent is in the wrong lane, follow him, but not to closely. This allows him to pass the traffic for you. Also, if he hits someone you can get out of he way if you are not too close. This is unlikely however, as the CPU follows the cars through a safer route. As long as you do not disturb him he will not hit anything. This will give you a faster and safer boost. Additionally, when you get a full boost meter, you can gain and use boost a lot faster by tapping A (Boost) button instead of holding it down and draining your boost all the way.
Drive on the wrong side of the road until your turbo (NOS) tank or bar is full.
If you are on a course that has a lot of bumps, do not drive the trucks, 1970's car, stock car, hotrod, or gangster. The best car for this are the Japanese muscle or the student driver car.
Try to get as close to the vehicle as you can when you have turbo. Then, use it and get in front of the car. Stay in front of it. It will try to get past you. When this happens, keep hitting it as it tries to pass. In the pursuit modes, you can win the race immediately if you force the other car into a head-on collision with traffic -- this will stop them quite nicely.
When you are about to hit the car you think will make the biggest crash, use the turbo and drive towards that car. Hit your brakes and do a power slide into the car. This should put you into the air. Note: This will not work on trucks. Also for easy money in Crash Course 6, select a car that catches air easily (such as the SUV). Start with a boost and burn out of the tunnel. Go all the way to the left and hit that car.
Learn which car to crash into first, then restart, do a boost start, then burn into it.
This trick works in one player and two player modes. When you are doing the crash zones, at the start immediately hold R for a boost. After a few seconds, press it again. This should give you more boost, which results in a faster speed and better crashes. Repeat this as many times as desired. Additionally, when you are doing Crash Zone 7 "Whip Up A Storm Of Metal And Glass", go to the right onto the dirt. You can have a wider angle to turn left at the intersection, and therefore have more speed for a greater crash.
When trying to achieve all gold medals in championship mode, if you fail to win one of the races, reset the GameCube before it auto-saves. You can then choose to continue the championship and restart at the race you failed to win, without having to replay (and win) all the previous races. Additionally, when competing in multi-race championships, it is often frustrating when you get a gold in the first race but fail the next. To avoid this, choose to return to the main menu after a successful race. Go to the options, select "Save/Load", and save to a backup profile slot. Reload your original profile. Attempt the race, and if you succeed, again save to a backup profile and load your original profile again. If you fail, load the backup profile.