From RANGER forum:

I posted my "dislike" of my boats performance in the "what are your numbers" forum with no replies. Figured I would mention it here and see what any RANGER owners have for thoughts on it. In the spring I took my boat 2.5 hours away to where I bought it to have the TPS looked on the 1998 200HP EFI merc. It got replaced and then the mechanic took me out for a ride on the rock river near the Quad cities. While he was playing with the hydraulic jack plate and hammering on the throttle he managed to hit around 67.7 mph GPS. My problem all fall, I can barely keep it at 55mph. Same gear, half tank of gas. What numbers should I be able to run with my R91? Granted I watched the mechanic spin 6200 rpms while I try to stay at or under 5900 r's but regardless I figured low 60's should be do-able right?