F-4C Phantom II:
-Max Speed 1645km/h at 13000m (13km). (Fully Loaded/armed)
-Theoretical max speed 1847km/h
-Most efficient altitude 4000-7500m.

The McDonnell Douglas F-4 Phantom II is an American two-seat, twin-engine, all-weather, long-range supersonic interceptor and fighter-bomber originally developed by McDonnell Aircraft for the United States Navy. Proving highly adaptable, it entered service with the Navy in 1961 before being adopted by the United States Marine Corps and the United States Air Force, for whom it became an important part of their air forces in the mid-1960s. The Phantom was produced from 1958 to 1981 with a total of 5,195 examples. This made it the most-produced American supersonic military aircraft in history and cemented its position as an icon among Cold War fighters.

Also this is probably my best jet so far.