Hi I have a 1989 mercury 150 XR4 that I had to replace the lower on. The original case was a small gearcase with a 1.87 gear ratio.I was able to get 75mph+ without hitting WOT. I replaced it with a large gearcase with a 2.o ratio and my old prop is too small in hub diameter. I am also getting prop blow out when trying to get on plane. I am running a 26 pitch prop SS What prop should I get to fit this lower unit? Once I get the boat on plane my WOT is at 5800 @ 60 mph. Thanks Rob
