The standard servos will be fine. I too would recommend a gasoline engine like the new Evolution 20CC. It's front a carb and comes with a wrap-around pitts muffler and sips fuel.<a href="http://www.horizonhobby.com/products/20gx-20cc-1-20-cu-in-gas-engine-EVOE20GX">
http://www.horizonhobby.com/products...ngine-EVOE20GX
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