The numbers don't add up.
The 4 blade must have been a 24 pitch prop. Otherwise you would have to
turn 6200 rpms w/ a 21 to get that speed.

Tony What's the gear ratio for the Evinrude 150 HP motor?
Thanks, Art



Assuming the 4 blade is a 24 pitch prop then that should be about your best
performance w/ this rig.
You could drop down to a 22 and get a few more rpms which will help w/ the
hole shot but it will slow you down on top end.

A 4 blade will usually be a few mph slower due to its less efficiency on top
end (it is much more efficient at lower rpms but not at high rpms).

As for the steering wheel pull, adjust the trim tab which is directly above
the prop so it is pointed straight in line w/ the boat. Sounds like someone
has pushed it full right which will cause the boat to push left. Keep
playing with it until you get it where you want it.

--
Tony
my boats at http://t.thomas.home.mchsi.com