Detroit and New York share the same timezone year-round. When it's 12:00 PM in New York, it's also 12:00 PM in Detroit. Both cities observe DST on the same schedule.
Both cities use Eastern Time (EST/EDT, UTC-5/-4). Michigan is one of the US states split between timezones, but Detroit is in Eastern Time.
Any time works! Business hours are identical. The 90-minute flight makes same-day business trips convenient between these cities.
Detroit is the historic home of the American auto industry (Ford, GM, Chrysler). Many automotive companies have offices in both Detroit and New York.