On Sun, 16 Sep 2007 13:11:02 -0400, DownTime
wrote:
Just got the boat back, with a new 10-inch jackplate and performance is
back to what it was originally. I recently learned more about jackplate
function and theory than I had previously considered. There's a bit more
to it them simply raising the motor up and down. 
Thanx again for your help and advice
Glad everything worked out for you.
Jackplates are fun to work with, but they can have some interesting
and completely unintended side effects if they aren't right.