A nigga coming down with blue and purple
from DJ Screw (Ft. Big Moe, Big Pokey, Bird, D-Mo, Haircut Joe, Key-C, K-Luv & Yungstar) – June 27th Freestyle Lyrics on Rap Genius
Meaning
“Screw blue” and of course, purple, are two popular color ways on cars in Houston.
The term Screw blue has been popularized from the color of Screw’s Impala:

The color purple, being representative of purple Promethazine-Codeine cough syrup, has become iconic in Houston’s Chopped and Screwed hip-hop subculture.
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