Type the following codes (without the quotes) when you are in the garage and then click on 'Fine Tune Specific Parts'.

Unlock $1,000,000
Type 'begformoney'

Unlock 'Drag Starr' Hauler's SD750:
Type 'dragstarr'

Unlock Balenr GT3 in your Garage:
Type 'bavariancheetah'

Unlock Duhen CDVC in your Garage:
Type 'racingforreal'

Unlock Einvagen 140GTA in your Garage:
Type 'xtremetuner'

Unlock Enula WRST in your Garage:
Type 'iloverallies'

Unlock Focer WRC in your Garage:
Type 'granturismo'

Unlock Furrano GTS in your Garage:
Type 'catchmywheels'

Unlock MC GTLE in your Garage:
Type 'americanmuscles'

Unlock Nonus GT2 in your Garage:
Type 'hellofromtokyo'

Unlock Prime DLH500 in your Garage:
Type 'primemyride'

3,000 Prestige points & 4 secret buttons in Club Info:
Type 'iamcoolguy'

Teleports to the Red Club and places you 1st in the club rating :
Type 'kickassreddevil'

Cash and Races:
Enter codes in the garage and press the tuning button to activate them. This cheat only works with the latest updates, patch 2.1.8 or higher.

BegForMoney - $100,000

Letmeroc - The Race Of Champions (You need $100,000).