Like smoke in the thinnest air, I open the Lamborghini
Hoping them crackers see me like look at that bastard Weezy
He's a beast, he's a dog, he's a mothafuckin' problem
Generally warmer substances, air for example, rise above cooler. When the air is “thin” (less dense than normal) it will rise even faster than normal. His doors, suicide, open up much fastes than normal, similar to how smoke rises on a hot day.
Wayne prays that his haters (here, cops) see the consequences of his success: luxury. While he passes, people whisper about how much of a boss the new money rapper is and how much he threatens the status quo.
In a larger sense, Wayne is celebrating the dynamic that defines his life: an extremely successful black kid from the ghetto flaunting it to the white world (whose penchant for buying iTunes giftcards, ironically, helped make him rich in the first place)
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