Including the notch the prophaft nuts are about 68 inches back from the running surface...,

Did you save the silver material for me out of the Nor-tech when you did the new interior like I asked you to?

You can always space it down right?

Cant space these drives down Kevin. But, I do have about 2 inches up or down on the extension boxes.

Are u gonna use the stock location to bolt drives on or are u reglassing transom?

Stock location, so its not really a big deal to move them up or down, just trying to get a starting point.

A normal #6 is 48" away from the transom and runs about 3 inches above the running surface. My props are about 60" from the transom.

So, just doing some basic math tell 3" divided by 48" = .0625 inches rise per inch of setback.

Using that number: .0625" X 60" of setback gives me 3.75 inches above the bottom.

I was looking for this same info a while back only for bravo set up on a 30 ft cat whit the xr its on the back and thinking to start at 3.5 " above the bottom to get the bullet out of the water to reduce drag it worked great on a outboard cat a friend did but could not find a lot info and response on the question ,most of the boats are set up 2" above the bottom max but I decided just to start at 3.5 " and then go down if it not work to find the sweet spot .

Very curious what idea coming by on this thread

This would assume that the water travelled in a straight path from the back of the boat, but I would believe the path would be slightly curved or rounded as the water returns to water level or above. Now speed would also determine how curved? This theory would bring the water up thus raise the projected shaft from 3.75 in above to possibly 4" above the running surface. (edited.. originally was thinking it would lower the shaft but bringing water up would raise it)

I will hafta check but if memory serves the Talon I use to race with Ed was at 3.5". Number sixes on boxes plus that hull had a pretty good size notch (built as an OB boat) so they were pretty high.

Dave the cats can usually run higher because they don't need any bow lift. I'm setting mine at about 3.5" with the ability to go all the way down to 1.5"