Hot Wheels: Velocity X Cheats

Unlock every car and track:
Press and hold R1 + L1 and push Circle, Square(2), Triangle, X in the main menu. You will hear the sound of an engine if you have entered the code correctly

Every car:
By collecting 11 Bonus Stunt items while completing Challenge 8.

Every world:
Find the Hidden Key while completing Challenge 18. The yellow key is in the Mines, across a trestle at the end of a tunnel.
User Cheat by Girl_Power

Every gadgets:
By hitting 25 Barrels while completing Challenge 7.
User Cheat by Girl_Power

Laser upgrade:
Finish every challenge, then unlock the "Timer Speed" cheat. Set it to 10% speed. After altering the difficulty level to very hard then finish Challenge 18. Get the "A+" rank to unlock the "Laser Upgrade" cheat.

Unlimited ammunition:
By hitting 50 Barrels while completing Challenge 18.

Unlimited health:
By hitting 179 Barrels while completing Challenge 17.

Unlimited turbo:
By collecting 8 Zappers while completing Challenge 4.

Timer speed:
By hitting 13 Detour Signs while completing Challenge 15.

Gadgets for completing challenges:

Challenge 1: Laser Cannon
Challenge 3: Sonic Boom
Challenge 4: Atom Blaster
Challenge 7: Freon Bomb
Challenge 9: Energy Shield
Challenge 10: Jet Booster
Challenge 13: Super Zapper
Challenge 15: Magnet Mine
Challenge 16: Doom Disks

Underworld Arena:
Finish Challenge 17.

Sho-Stopper vehicle:
Finish Challenge 6.

Surf Crate vehicle:
Finish Challenge 12.

Krazy 8s vehicle:
Finish Challenge 18.

HW Prototype vehicle:
Finish every mission in adventure mode.

Underworld Track:
Finish Challenge 2.

Glacier Track:
Finish Challenge 11.

Sewer Pipe Arena:
Finish Challenge 5.

Crankshaft Docks:
Finish Challenge 8.

Treadwell Plaza:
Finish Challenge 14.