Ich hoffe, ich verstoße mit dem was jetzt kommt, nicht gegen irgendwelche Regeln:
Diesen Beitrag habe ich in einem Forum gefunden, in dem es um die
78"-Extra von EF geht - aber darum geht es mir nicht, der Autor hat offensichtlich die Antriebe auf dem Prüfstand gehabt und die Leistungen ermittelt - und da EF vorschlägt 1700-2000 W in die Extra zu packen, erscheint der Antrieb mit 5325/18 an 8s als sehr geeignet - natürlich kleine (4000er) 8s:
"1.) The 5320/18 is not the best choice for the Extra and my Sukhoi, although Donatas has used it for the World Air Games. Standard battery setup is 6s, best suited props are the APC-E 20x8 or 19x10 for windy conditions. With that setup you'll only have 1600 watts at 75 amps. To my mind this motor should be used in slightly lighter models than the Extra with a maximum of 70'' wingspan and not more than 4kg / 8,5lbs of weight. With that power combo the plane will 3D easily, but will lack power for pattern flying, especially in windy conditions. This setup also requires high quality batteries that hold voltage well, otherwise your fun will be over just after a few minutes of flying due to power loss. Another option would be adding one cell to have 7s.
2.) The 5325/16 is 5mm longer than the 5320, weighs 75g more and also has a slightly lower kV. With a 6s battery the best suited prop is the APC-E 22x10 for 3D, alternatively you can also try the 20x12 or 20x13 for windy conditions or pattern flying. With that setup you'll have about 1700 watts at 80 amps, which is not much more than the 5320. The only advantage to the smaller brother is the larger prop you can use. With weak batteries you'll also notice a fast power loss, therefore I have also tried with motor with 7s and even 8s, of course you have to prop down then. My favourite is a XOAR electric 19x8 on 8s, which makes the plane a 3D monster. Needless to say that you have to be extremely careful on the throttle and your ESC must also able to handle the power draw of up to 110A!
3.) Probably the best choice for the Extra is the 5325/18 on 8s. Depending on the prop this setup will produce 2200 watts @ 75A. Prop options are 19x12 for pattern flying, an APC-E 20x10 for free-style flying or the 20x11 as a compromise of both worlds. With light 8s batteries and capacities of about 4000mAh, you'll have a perfect power to weight ratio and flight times of at least 7 minutes."
Hier der Link zum Originalbeitrag:
http://www.rcgroups.com/forums/showpost.php?p=13712655&postcount=978