I wanted an easy way to swap motors on my Atomrc Dolphin so I made this motor mount combo.  

Assembly:

Motor Mount:

• Use a soldering iron to push 4 M3 heat inserts in.
• Glue into plane with E6000 or Hot Glue

Motor Plate:

Print the desired motor plate. I have provided multiple versions for the most popular motor bolt patterns: 16x16(quad), 19x19(quad), and 19x16(Sunnysky).  There are extended versions for 16x and 19x if you need to shift a little weight to the back.

• Fit m3 bolts through the outside holes, M3x10 or 12
• Fit m3x6-8 to mount motor. I use the short bolts included with the motor.

This 2807 1700kv Eco for example: https://www.readymaderc.com/products/details/emax-eco-II-2807-brushless-motor-1700kv

Running with a 7x4 prop seems to be a solid combo.  I am waiting for my new SunnySkys to show up and when they do I will make a new motor plate so I can swap that motor in.