Where to go now???

[Mytmerc83]

So I have recently built a goldwing/skyline Sbach 343 70. It has a 60" wing span and weighs in at 6.5lbs. I run a evolution 10cc as I worried it's not enough. Flys ok but 3d is suffering can not hold a hover at all, falls out. So I'm not sure where to go from here or what to do?? From what I have read a 15cc is too much for this plane a will tear it apart. Will a evolution .61nx make more power?? I have another twist 40 so the 10cc will just go onto this one. Any thoughts or comments are welcome. Thanks!!

 

[Mytmerc83]

Thought I'd throw a picture up.

 

[mjmccarron]

The Sbach spec calls for a .46 - .52 glow engine so the .60 Evolution should be a good choice. What puzzles me is that your 10cc (.61ci) gas engine should output more power than a comparable glow engine. Gasoline has 60% more potential energy than ethanol. Is it much heavier than the glow version? I am considering the 10GX for a project I'm working on. It seems far more economical but if it lacks power I may need to reconsider.

 

[Mytmerc83]

I think at 6.5lbs it's pushing the limits of the motor, gas or nitro. On the twist at 5.5lbs could do everything I asked it. Pull out of a hover was sluggish!! Yes the fuel cost and efficiency is great, on a full tank in the twist (has a bigger tank then the sbach) I could fly 45mins. Think I might put a .75 on the sbach?

 

[Mytmerc83]

So been thinking on this all day definitely putting the plane on a diet, but I'm wondering about the exhaust deflector I installed to drop the exhaust out the bottom of the cowl. could it be a little too small and restricting exhaust? there for loss in power?? I have noticed the rpm's will not hit as high as when on the twist.....same prop, same set up, only added the deflector? I did note to my son that it quited the motor down a fair bit. I will remove the deflector tonight and run it up see if that's an issue will also lose and lighten up a couple things. Should all help i hope.