VFE
this is what I found and used for the 747's
21 747-400: Either 4 PW 4052 rated at 50,000 or 4 RB211-524 H/T at 60,000
6 747-400F:RB211-524 H/T at 60,000 pounds per engine
6 747-400ERF: 4 PW 4062 rated at 62,000 pounds per engine
12 747-400BCF: RB211-524 H/T at 60,000 pounds per engine