Drive height?

[clancy72]

I am swapping out my V/P 280 for a later model SX, reglassing the transom. Does anyone have a template or height guide for optimum speed performance? I know the higher the unit the less the drag, but what is too high. I've measured my old outdrive and recorded the distance, should i just use the same height?

 

[clancy72]

Re: Drive height?

Here is a pic of the current set-up. Water comes up to the swim platforms with 1/2 load of fuel (30 gallons) . The boat currently has a great holeshot.

 

[wire2]

Re: Drive height?

The rule of thumb is that the cavitation plate should be level with the lowest part of the hull.

You *can* raise the outdrive above that for less drag but you risk prop cavitation, finicky trim settings, loss of bite on turns.

There's a hydraulic device available to raise/lower outboards but can't be used on an I/O for obvious reasons.