FaceDeAce

Hi,

I am gearing up to begin the build on this plane. Looks like a fantastic kit. My question is one of power choice. How much power can this plane handle? I see many have gone with a 120 four stroke.

I've done a little research. The full scale Extra power to weight ratio is around 0.2 hp per lb. The Extra I am building should come out 7.5-8.5 lb. So I figure I need a minimum of 1.6 hp to be scale. That's your base 91 four stroke / 60 2 stroke.

However, my goal is to be overpowered for access to mild 3D capabilities. So at +50% that would be a 2.5 hp engine. Therefore I am looking at a Saito 150-180 four stroke or a 1.08 - 1.50 2 stroke. Overpowering it would boil down to diligent throttle management.

So, what is the maximum power ever installed and tested in this kit?

bako

wait wait. don't install more that 120. cause it will be too havey for 3d. only Hp means nothing at all. I think saito 100 is well, as people say and they are wright. it weights same as 91. I'm going to install magnum 91 4stoke with 15X4 prop. such setup has thrust about
4.6-5 kg, depending on nitro%.