Re: 1985 bayliner capri 2.1 volvo penta 270 sterndrive
We need the diameter (and)pitch of the props. Hopefully you can remember the old prop rpm and speed as well as the new.
A gps is best for speed.
Normally a 1/2" change in diameter will result in about 100 rpm change.
Tweaking would involve your present performance numbers.Like if you had high slip, try to g figure why and perhaps a prop change. Not enough rpm or too much rpm.Solving slow hole shot or excessive bow rise.
With those numbers we may be able to tell if your setup works.