Green’s Dictionary of Slang

(US black) a Cadillac.

1934		Z.N. Hurston Jonah’s Gourd Vine (1995) 164: Everybody in town is talkin’ bout dis blue and silver ‘Kitty’.
1945		C. Himes If He Hollers 49: [W]e talked about cars [...] The boy from Frisco said, ‘Of course if I had my way I’d take a Kitty’.
1969		‘Iceberg Slim’ Pimp 121: I just remembered I left my ‘kitty’s’ slammer open.
1972		E. Folb Urban Black Argot 141: Kitty / Cat / Kitty Cat a Cadillac.
1980		E. Folb Runnin’ Down Some Lines 84: By far the most popular car among those I met was the Cadillac – variously referred to in the vernacular as the [...] kitty, cat, kitty cat.
1983		S. King Christine 409: Jumped in my kitty and drove her far – Bob Segar.