A Combustian engine. Called a V8 because it has 8 cylanders arranged in a "V" formation (if you look at it from the front or back), with 4 cylanders on each side. Very common in muscle cars from the 60s and early 70s, the V8 is still a popular motor among Domestic car enthusiasts.
Both the new Ford Mustang GT and Chevrolet Corvette have V8 engines.
Usually used to describe someone or something from or similar to Long Island. This is because the area code for much of Long Island is 516. Somebody from the 516 area code, especially after moving elsewhere, is called a 516er.
Roughly half of the population of Florida is comprised of 516ers.