You can get Racing Snails here for Poser and Daz, although they’re not as cool as those in the excellent new movie Turbo. But you could probably have a lot of fun customising them with jet packs and suchlike, scavenged from other content.
And I’d suggest Ollie the toon octopus as the perfect TV race commentator for your racetrack.
Carrara 8 is DAZ Studio's official 'big sister' software.
Carrara loads all DAZ and Poser characters and scenes,
and supports LuxRender for top-quality realistic rendering.