No much of a fan of most pre-90s stuff. But here's a couple hiphop tracks from the 80s that stand out to me for various reasons, even if they're dated (in some ways they're actually more dynamic than some of the modern rap stuff).
Date: 1983
Location: Queens/Bronx New York City
Rap style: Very simple rap
Sound: barebones breakdance
Synopsis: A "song" with no guitar, no bassline, no melody, no singing, and no chorus. Just a staccato beat. Record companies wondered, "what is this supposed to be???" But teens in the burgeoning breakdance scene in NYC were digging it.
https://youtube.com/watch?v=u6h0WO3_NsQ
Date: 1984
Location: South Centra L.A.
Rap style: Simple
Sound: electrobeat/breakdance
https://youtube.com/watch?v=tNDfOlZSLBM
https://youtube.com/watch?v=iB9Km7zIrK8
Date: 1987
Location: Harlem New York City
Rap style: Wordsmith
Sound: early raw/organic hiphop
https://youtube.com/watch?v=a91rv2vTl4o
Honorable mentions to PE, BDP, Beasties for some good tracks back then too.