?? X Dimension

[Airslot]

This was bugging me so I did a little more reading. Typically, "X-Dimension" is a term reserved for use when discussing stern drive mounting height. It is the relationship of the prop shaft centerline to the boats running surface. This is generally difficult to modify in a sterndrive. They also make drive spacers for more setback for high performance use. When mounting outboards, the most impotant measurement is shaft length. It must match the transom height which, is typically 25" for V-20, but there are boats like my V-20 which has a 20 inch transom. For anybody wondering, raising the motor one bolt hole is the equivalent of 13/16". For those running brackets, a good starting point is to raise the vent plate 1" above the hull bottom for each 12" of setback.

Just some more info.

Airtslot