I just put a mercury 9.9 (mid 90's, has the shifter integrated with the throttle) pushes my 12' starcraft like a rocket, even porpoised at wide open! 
Anyway, it pulls to the left at speed only, as if it wants to turn right. I see a screw with something missing under the cavitation plate, just behind the water inlet port. Does this little motor have a trim tab?
One more while I got you.... the tell tale acts like theres a thermostat in there, even after changing impeller. Does it?
Thanks guys,
Scott
Anyway, it pulls to the left at speed only, as if it wants to turn right. I see a screw with something missing under the cavitation plate, just behind the water inlet port. Does this little motor have a trim tab?
One more while I got you.... the tell tale acts like theres a thermostat in there, even after changing impeller. Does it?
Thanks guys,
Scott