Can I make a Hacker A20-20L with a 25 ESC That I have. Work in a Great Planes Sukhoi 3D ARF ? Or is it just a waste of time and money.Could use all the Help I can get on no gearbox - gearbox . battery size Prop & so on.

http://www.rctoys.com/rc-toys-and-pa...RS-HACKER.html
Hacker A20-20L EVO Brushless Outrunner RC Motor, 55g, 200W, 1022 RPM/Volt
SKU: HA-A20-20L With A The Phoenix-25 ESC can be used in aircraft and helicopter installations and is ideal for Astro 020, Astro 05, Aveox 2713/xx, Mega 1615/xx, , HiMaxx 2025, 2015, MP Jet Brushless, Jeti Phasor (under 25 amps)and Hacker B-20 and B-40 motor applications.
With it's feature-rich user settings, the Phoenix-25 can be set up for almost any installation using 25 amps or less. Three timing settings, over-current protection, helicopter govenor mode, five cut-off voltages and more! It even fits comfortably in narrow sport fuselages.Perfect for use in your 12-18 oz Parkflyer or Slowflyer RC model airplane, the Hacker A2

Great Planes Sukhoi 3D ARF http://www.rcgroups.com/forums/showthread.php?t=235649
Wingspan: 39.4" (1000mm) Wing Area: 555 sq in (36 sq dm) Weight: 26oz (735g) Wing Loading: 4.9 oz/sq ft (15 g/sq dm) Motor: Kontronik Fun 400-36 Brushless Motor w/4.2:1 Gear Drive Esc: Kontronik Smile 30-6-12 Radio: 4-5 Channel

If the motor and ESC can fit your airframe they should be fine. You have roughly the right power (200W), big enough ESC to handle 200W on 3S lipo, and assuming the motor and ESC are not unusually heavy for their size, they should fly the plane pretty well.

Hope this helps...Chris