727 RPM Drop @ Shift???

Hello All!

For a 727 behind a 600ish HP 440 with a 5000 stall, how much would you expect the RPM's to during a shift at WOT?

Ours is dropping about 800 RPM when shifting at 6500...

Wondering if that sound about right or should it be dropping more to get into the torque range?

Thanks