Luke already posted the original video to the main site so I couldn't really fit this in there, which is a damn shame because this Chamillionaire X Mario Kart 8 mashup is near perfect as far as one-off rap-infused jokes about video games go.
Also fun fact I just learned: the original name of the song is actually just "Ridin,'" not "Ridin' Dirty" as I've been lead to believe. From the song's wikipedia entry:
Its title is often incorrectly assumed to be "Ridin' Dirty", due to the chorus. The lyrics concern racial profiling and police brutality, as well as the stereotyping of African-Americans driving a vehicle with drugs or other contraband on the inside ("Riding dirty").
I guess Luigi doesn't really have to deal many of the horrors described in Chamillionaire's classic. But he wouldn't be the first white guy to crank the song when it comes on the radio, racing against Waluigi or not.