I have built a prototype octocopter with a large central prop (19x10) powered by a 35cc engine (so technically a nonacopter?). The engine provides most of the thrust and the 8 electric motors are primarily for control, thus decreasing the power usage and increasing flight time.
The motors I am currently using were from an old X8+ and just aren't up to the task. For safety I need motors that can lift the whole drone (max. 7kgs) easily when the engine is not running and can hold their own against the the power of the engine-driven prop when it is.
Battery - 4S 10000mAh
Prop size - max. 11x4.7 (due to clearance)
ESCs and Motors as required
So far I have found a Leopard motor here that seems promising - spec sheet says that with an 11x7 prop and 4S battery it can provide 1.6kgs thrust, drawing 19.2A (289W). So the drone should hover at roughly 75% throttle. My eCalc specs here.
Does anyone know of other motors that can provide a similar thrust or higher, given this setup? I have been using eCalc to check but it is a slow process and some of motors I am finding are not listed. If anyone has previously found motors that lift up to 2kgs each and know how they perform, I would be very grateful if you could please recommend them to me.
Also, do the results from eCalc seem acceptable? Aside from the throttle which ideally would be a bit lower, it seems ok to me but I have only just started using it.