With a designed speed of 128 mph, the fastest of these rides is Kingda Ka at Six Flags in New Jersey
[DOC] [TLE] Six Flags Great Adventure Will Launch Zumanjaro Inside Kingda Ka ... [PAR] Aug 30, 2013 ... Six Flags Great Adventure in Jackson, NJ will debut new thrill ride ... Zumanjaro 
Drop of Doom will be built on the Jackson theme park's tallest, fastest coaster 
Kingda Ka dropping riders 415 feet at speeds of up to 90 mph.