angry birds go level 6 kart? how?

[kinghamster]

does somebody upgraded there kart to LEVEL 6???i know the maximum level is 4 but i saw it on this website: http://angrybirds.wikia.com/wiki/Stunt i just wanted to know what is the level 4 name of Weaver XT but while reading i sundently saw 6.Shoemerang (Level 6) i wonder if its true but if its true can you help and tell me on how to upgrade my kart to level 6???i really needed this kart

Topic

[burpie]

All of the free karts max out at level 4. The Shoemerang is a cash-kart.

[kinghamster]

are you sure??check the website so you know what i mean