Hey guys I have a question for you. I have a buddy at the field who has a 40 size UCD with a YS 63. What are the optimal props for this engine for 3D performance??

I run a APC 13x4W on my Flip 3D/YS63 combo with great vertical performance. The throttle responce is instant and it leaps out of a hover. Awesome combo.

APC 14x4W

I agree, if you run 30% heli fuel the 14x4W, if 20% the 13x4.

14/4 works for me.

Thanks for the replies fellas, I'll pass it on. Hes flying a 13x4 right now. I flew it last night and it wouldnt quite leap out of a hover with it but the engine is brand new so maybe a little break in time will do the trick.

My YS 63FZ will pull a 14-4W with 30% nitro but the 13-4W spools up much faster. The 14-4W works better in the cooler temperatures (below 70F).

My YS.63 is the new one and in my flip it pulls vertical on under 1/3 throttle with a 14x4w and hovering is a breeze with it. Much better than the 12x6 I used to break it in with. But I just love it, it's almost stopping me from getting an electric motor for my C140.

I'm running Master airscrew 13x6 K-series prop on Powermaster 20/20 mix.

What kind of RPM's are you pulling and at what elevation? I gotta try one of those props one of these days.

I'm not sure, i would have to check that next time i fly. If i remember corectly, the Tach was reading "120". Feel free to slap me, but I'm not sure if that means 1200 or 12000.

It's probably 12,000 RPM. That's a little high but I'm sure you only use full throttle in bursts. YS says to prop them for 11,500 RPM peak. My APC 13-4W peaks at about 11,400 on WildCat 30% but I have it set pretty rich. Have you ever tried the 13-4W? I'd like to try that K series 13-6. Maybe the next time I'm at the LHS, I'll pick one up.

i have not tried a 13x4W i wouldnt mind trying one though.