Travis, the #1 rule for screw-ups in people using bigger engines in their planes for 3D is they never remember a factor called weight. I'm willing to bet my UCD vs yours that mine will fly MUCH better than yours simply because the all up weight in mine is only 7.11 lbs.

Again, *I* have a little over 2:1 power to weight ratio, but that's because I don't fly at sea level. If you're closer to sea level and if you put in a little work in to it, you can easily achieve 3:1 with a 120.

The trick is you MUST reduce as much weight as possible !!!

What I did to my UCD was the following:

-uncovered
-drilled tons of holes to the fuselage
-drilled tons of holes to the wing
-removed about 80% of each cap-strip in the wing
-drilled tons of holes in the landing-gear (should have gone carbon)
-recovered plane without any overlapping monokote / econokote
-removed cowling
-changed firewall to a much lighter one
-used 4 HS-77 (wings and elevator) servos which are lighter, stronger and more powerful servos than standard servos
-used HS-55 for throttle
-used a Micron 6ch receiver (extremely light)
-used 1 Futaba 9402 for Rudder ... should have gone with something lighter but this is what I had around.
-used a NiMH 1200 mah battery
-used contest-grade balsa to make a new "bottom wing lid" or the part that makes up for the fuselage bottom in the wing

Keep in mind APC props are _VERY_ heavy .... try and get the prop of your choice in wood.

To reduce much more weight, I could have redone the vertical tail, rudder, horizontal tail and elevator using contest-grade balsa and carbon fiber but I figured I was already with in my target weight.

One thing you're obviously failing to understand is that with a 180, you will either need to move the complete firewall back about 2" (maybe even more) or add tons of tail weight to get a nice 5.5" CG ...

My only word of advice is unless you do things right, your plane will NEVER out-fly mine ... If you can get the all up weight down to no more than 7.4 lbs _WITH_ the 180, you'll have yourself an excellent plane with a 4.5:1 power to weight ratio.

Your 3+:1 can _EASILY_ be done with a 120 and a little work and you might even be able to push that up to 5:1 with a 180. On the other hand, its also very easy to put in a Moki 180 and have a power-to-weight ratio of only 1.5:1 (because of the lead you'll need in the back of the fuse)

I hope all of this helps you somewhat and you make things right!

Please keep us informed on how things go.