Gran Turismo 3 Cheats :
Cheats - Secrets List
by Unregistered Apr 25, 2005
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.
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