Before you make a motor choice get an all up weight of your airframe. The F90 varies a lot in weight. There are heavy and light ones. Mine is 10 pounds (typical F90 with 32 oz power package) with an OS108 and power is OK at sea level. It would be better with an OS160. The motors you are looking at would not be a good choice for my (or the typical)F90. The F90 should be named the F140.