Conversion of the GP Extra 300S with Axi motor
 

Dear Friends,

I would like to know what Axi motor should I use in a conversion of GP Extra 300S .40, how many cells and ESC. Could I use the Axi radial mount? Have I reduce the weigth of this plane?

Thanks
Érico

RE: Conversion of the GP Extra 300S with Axi motor
 

A 14-cell NiCd/NiMH, or 4S LiPoly seems to work well on most .40-size sport plane conversions. For motor, either the 2826/12 or 4120/14, propped to draw about 40 Amps at full throttle. I explain how I got to these numbers in many many threads.

www.modelmotors.cz has application tables for all their motors. The 4120/14 would be better in cases where you need a little extra nose weight, and it spins a larger-diameter prop, 12" or 13" on the same power as the smaller motor. The 2826/12 is a little lighter, a little less expensive, but it's not built to take 40 Amps constantly, and it only spins a 10" or 11" prop.

RE: Conversion of the GP Extra 300S with Axi motor
 

OK. Thanks Matt. I will try this configuration but, in your opinion what´s the best for a model like this? The 2826/12 or 4120/14 ?? Both will fly well this model?

Thanks again
Érico

RE: Conversion of the GP Extra 300S with Axi motor
 

The 4120 imho.

John

RE: Conversion of the GP Extra 300S with Axi motor
 

is this the same as the Black Horse Extra / Graupner Extra? If so you need to add rigging to the stab... it flies off othervise ;)

RE: Conversion of the GP Extra 300S with Axi motor
 

Both will fly this model well. The difference will be like a .40 2-stroke versus a .70 4-stroke, if you're familiar with glow engines. You'll have better acceleration with the bigger prop on the 4120/14, but the 2826/12 will be lighter and less expensive.

RE: Conversion of the GP Extra 300S with Axi motor
 

I think that you'll be pushing the 2826 pretty hard and won't have any extra room for that little touch of extra power. While the 4120 is heavier, the last econversion I did came out tail heavy anyway. It required that I add nose weight and I hate to do that. Both should fly the plane anyway.

John

RE: Conversion of the GP Extra 300S with Axi motor
 

I don´t understand one think: If I use the light motor, I have to add wieght to tail?? But if I positioned the battery to compensate, this kind of think is good for that aplication? Do you use, in your opinion, which motor for the conversion of GP Extra 300S? The 4120 ou 2826? Thinking on the model´s balance and performance.

Thanks
Érico