The Datsun 280z was put into production from 1975-1978. It had better emission standards than previous models so it could be sold in the United States. The 280Z was named for it’s 2.8 liter inline-4 engine.
Why aren’t there any Datsuns now? Well Nissan phased out the Datsun brand in March 1986. The Datsun name is most famous for the 510, Fairlady roadsters and later the Fairlady 240Z coupes. You young’uns are probably more familiar with the Nissan 300ZX, 350Z, and the current 370Z.  This 280Z was spotted downtown Sioux Falls.