Et Al,

 

The old (circa 1989) Lancair 320/360 construction manual says 1 inch below the extension of the longeron at FS 80.  They also recommend a #40 drill for the hole (.098"). 

 

After trying to use pitots with built in static ports and failing, I put the Lancair ports on each side of the airplane. The lines move forward and up one inch (just below the longeron), then down the seat backs and they meet on the flap motor side,  there is one tee that leads to a 6" "drain" (never drained) and another that joins the lines and then is routed forward.  I have never seen water in these lines.  Bill "Ice Man" Harrelson has never seen them ice over.  If I could do it over, I would drill smaller holes since the wee AOA hole in the top of the wing has never taken water either - even when parked during a large drop Florida thunderstorm.

 

May the ambient be true to you!