I won a Smartech Pegasus heli at last year's Northeast Helicopter Jamboree up here in the Rochester NY area. It's my first heli, and with the help of my brother, we got it flying at his club's open house a few weeks ago.

The engine on this thing is a persnickety little Chinese .18 monster truck engine, complete with tuned pipe. Low-speed needle is all the way in, it's still way too rich on the idle, and won't start without pinching the fuel line.

But, that's another show.

I'm well-versed in converting electric airplanes, but my electric helicopter conversion knowledge isn't great... My gut tells me that it's going to take a hot little outrunner like an AXi 2820/8 and a 3S or 4S pack around 3200mAh, but I'm a lot fuzzy on the gearing.

So, any tricks to figuring this out?

There is a speed calculator link on this site, you can use this to calculate RPM on, Engine, Main rotor, and tail rotor. Try a search for "HeliWizard Calculator".