110,000 Credits In 30 Minutes
Buy a Toyota Integra Type-R and upgrade it to the maximum. Now go to the Type-R meeting in the begginer leauge. Do the series race (5 races) and you get 5,000 for every race and 10,000 at the end. 35,000 already! Now you get an Acura worth 75,000. Sell this and you have gained 110,000 credits in 30 minutes. Easy money!

75% completion
Complete 75% of the game and you will be rewarded with a Mazda 787B.

Accelerate faster
If your gears are in automatic then hold R1 when you start to move and wait to the Rev gets to the Red bit and release ( You must release it - otherwise the car wont change gear! )

All Japanese GT Championship prize (Amateur League)
Win the All Japanese GT Championship in the Amateur League to unlock the Honda Arta NSX JGTC and Denso Supra Race Car.

Altezza Championship Race prize (Amateur League)
Win the Altezza Championship Race in the Amateur League to unlock Tom's X540 Chaser and Toyota Vitz RS 1.5.

Best way to start the game
Your first car should be the PT cruiser, then save up and buy a chevrolet camaro SS, then buy a Toyota Supra. Save up and fully tune it, it will have around 1000bhp! Then make sure you have the IA license and enter the super speedway endurance race. This will take around an hour, it will then win you a F1 car and 200000cr!! The F1 car can enter and easily win most races. Be warned though because you may not win the F1 car first time round, but both times I have tried, I did.

Bonus tracks
Complete each tier of tracks in arcade mode on any difficulty setting to unlock the next tier of tracks:

Tier 1
Super Speedway, Midfield Raceway, Smokey Mountain, Swiss Alps, Trial Mountain, Midfield Raceway II.

Tier 2
Smokey Mountain II, Tokyo R246, Grand Valley Speedway, Laguna Seca Raceway, Rome Circuit, Tahiti Circuit.

Tier 3
Swiss Alps II, Trial Mountain II, Deep Forest Raceway II, Special Stage Route 5, Seattle Circuit, Test Course.

Corvette C5R
Simply beat 50% of the simulation game and you'll be given a Corvette C5R.

CorvetteZo6 with 793 horsepower
It's not really a cheat, but it's a hint. Buy a CorvetteZo6 for $54,000, and upgrade it to the maximum. Then you're ready to go.

Creation of dream car.
You need to have two PS2 Memory Cards for this to work. Sell all the cars you've won/acquired except the one you want to modify in the Slot 1 game but save the game afterwards to Slot 2. Use the cash from the sale to ramp up your car and save the game to Slot 2 again.

Now load the game in Slot 1 (the game that still has all your cars) and ask to trade with Slot 2. Once you finalise the trade, you can save the game to Slot 1 and copy the Slot 1 GT3 game block to Slot 2 and repeat the process.

Deutsche Tourenwagen Challenge prize (Amateur League)
Win the Deutsche Tourenwagen Challenge in the Amateur League to unlock the Volkswagen Lupo Cup Car, Volkswagen Beetle Cup Racer, Astra Touring Car, and RUF 3400S.

Dream Car Championship prize (Amateur League)
Win the Dream Car Championship in the Amateur League to unlock the Mitsubishi FTO LM Race Car and Mazda RX7 LM Race Car.

Dream Car Championship prize (Professional League)
Dream Car Championship in the Professional League to unlock the Toyota GT1, Panoz Esperante GTR, FTO LM Race Car, and F090/s.

European Championship prize (Amateur League)
Win the European Championship in the Amateur League to unlock the Lotus Elise 190, Nissan GTR V-Spec, Gillet Vertigo Race Car, and Mini Cooper 1.3I.

Get a F1
After you have sot the ia licence go to endurance races and and do the Super Speed Way Circuit (100 laps) after you finish you should win it. (if not do the race until you do)

Gran Turismo All-Stars prize (Amateur League)
Win the Gran Turismo All-Stars in the Amateur League to unlock the Mine's GT-R-N1 V-spec and Raybrig NSX.

Gran Turismo World Championship prize (Amateur League)
Win the Gran Turismo World Championship in the Amateur League to unlock the Nissan C-West Razo Silvia, Nissan Z Concept car, Toyota GT1 Road Car, and Mazda RX8.

Grand Turismo World Championship prize (Beginner League)
Win the Grand Turismo World Championship in the Beginner League to unlock the Toyota Celica GT-Four, Mitsubishi Lancer Evolution VI GSR, Mazda Miata, and Nissan Skyline GTR V-spec II.

Hot rod car for car dealers price
First off you must have 2 ps2 memory cards. Second you should get about 100,000-2 mill.[depending on the car].

Next-load data off mem card 1. Go to car and buy it then use anymoney you have left to hike up the hp [horse power] to your desired level. Then save that memory to slot 2's memory card.

After that saves go to the main menu and go to load and load data from memory slot 1 go to your home hit trade load cars from slot 2 and scroll down to the car you had gotten really powerful and buy it for the car dealer's price

Example-

I made myself 400,000and went to he dealer ship. I bought a dodge viper[any car works I just like the viper] i bought the things in order,

1. na tune up 1
2. racing muffler
3. na tune up 2
4. port and polish
5. full engine balancing
6. racing computer chip
7. na tune up 3

Then i bought the drivetrain stuff if you don't want to u dont have to but I recomend you do buy atleast the full racing tranmission. and after i got the drive train things I bought the brakes and suspension upgrades and made it almost perfect.

After i bought all the upgrades i spent maybe 350,000 saved to my second memory card. got my $400,000 back by loading and went to my home clicked on trade loaded the cars from slot 2 and bought the viper for estimated 80,000. After i checked the horepower of my viper and it had about 1080 horse power and i took it to the oil change place and changed it. After i went back to my garage and looked it then had 1110 horse power.

Well hope it works for you like it did for me, and if u cant get the na tune-up replace those with the turbo kits in the exact oder 1,2,3,and 4 if possible. Good Luck!

How to get the Mazda 787B race car
If you win the 'Like the Wind' race at the Test Course you are given the Mazda 787B race car.

Japanese Championship prize (Amateur League
Win the Japanese Championship prize in the Amateur League to unlock the Subaru Impreza Sedan WRX STi Version VI, Chevy Camaro Race Car, Audi TT 1.8T Quattro, and Mazda RX7 Type RS.

Japanese Championship prize (Amateur League)
Win the Japanese Championship prize in the Amateur League to unlock the Mazda RX-7 Type RZ, Mitsubishi Evolution IV GSR, FTO GP Version R, and Subaru Impreza WRX Sti Version VI Wagon.

Mazda Eunos Roadster
To unlock the Mazda Eunos Roadster, complete the cupman cup with gold medals in all three races.

Mazda Roadster RS
To unlock the Mazda Roadster RS, complete the spider and roadster cups with gold medals in all races.

More Money More Money!
This tip keeps you in the millions,, you need a fast car and a steering wheel with pedals, in my example I use the escudo Pikes Peak version (won from finishing all the rally races). Once you have the car and the steering wheel. You go to the endurance races and choose the last one (test track 150) start the race put something heavy on the gas pedal and turn the wheel to the right and walk away for 53 min. The car will ride the wall the whole time, dont worry about the tires on this car its still fast, when you get back you've got 200,000CR and a new car! works every time!

Nissan Silvia K's 1800cc
To unlock the Nissan Silvia K's 1800cc, win the beginner FR Challenge series.

Pro mode
Goto arcade mode. Select the HARD option on the selection screen of difficulty. Press down on L1 and R1 until it shifts to the Pro mode.

Quick easy money (350000cr)
The championship which gets you the best lap to money ratio is the amatuer european championship. In this championship you can get 350000cr form 4 races of 3 laps. To do this you race the first 4 then save (before you go onto the last race) then quit the last race. To get 350000cr you have to win the vertigo racecar. Keep on loading until you get it and then sell it for 300000cr.

Silver Honda CRX Del Sol SiR
To unlock Silver Honda CRX Del Sol SiR, win the beginner race of NA Sports series.

Super Speedway 150 Miles prize (Endurance)
Win the Super Speedway 150 Miles prize in Endurance to unlock the Chevrolet Corvette C5R, Tickford Falcon XR8 Race Car, and F090/S.

Team ORECA Dodge Viper GTSR
Win all Golds in the Amateur League.

Tommy Kaira ZZII
Win the MR Challenge in the Professional League.

Toyota Celica Rally Car
Win the Tahiti Challenge of Rally in Rally.

Toyota Celica SS-II
Win the Altezza Race in the Beginner League.

Toyota Corolla Rally Car
Win the Tahiti Challenge of Rally II in Rally.

Toyota MR-S S Edition
Win the MR Challenge in the Beginner League.

Toyota Sprinter Truendo GT-Apex
To unlock the Toyota Sprinter Truendo GT-Apex, complete the Sunday Cup with gold medals in all three races.

Toyota Vitz RS 1.5
Win the Vitz Race in the Beginner League.

Type R Meeting Prize (Amateur League)
Win the Type R Meeting in the Amateur League you will unlock the Mugen S2000, Spoon Sports S2000, Honda S2000, and/or the NSX Type R.

Volkswagen New Beetle RSi
Win the Beetle Cup in the Beginner League.

Zoom
At the car select screen you can hold the R1 button to zoom in on the available car. If you hold R1 + R2 you will zoom in even further (this will demonstrate the amazing ability of the PS2 to "push" graphics).