Calculate most efficient motor placement

[ltdcruze]

If I know how much thrust my motor & prop combo gives off, is there a way to calculate where it would be the most effective on a plane with 3 other motors. I would imagine that some overlap would waste thrust and spaced too far apart there could be not enough thrust hindering performance. The circles in the drawing represent motors and the square represents a plane to add an illustration to my hard to explain question.

[fluxno]

i _think_ its most efficient with the motors as far away from each others, because i've heard something about "tip vortexes" that makes turbulense in the water. i also think it would be less "wobbly" with the motors further away.

I'm not good at mathematics, but more focused about testing and finding out.

And the efficiency can be compared with measuring the amp the motors draw. ie a less efficient design will pull more amps at the same thrust value.

This test Kjetil performed shows how the amps skyrocket when a big propeller is mounted, and it would be more efficient with 2 thursters with small propeller than one with a big propeller viewtopic.php?f=3&t=900