3D Max, Most powerfull engine for Helis - 4.8 HP
Pump Bulb Carburator, Lightened Ported Piston, Balanced Flywheel. High compressed ported cylinder, Metal Recoil ring.

Performance evaluation:

Without a doubt, there is something good cooking with the Hanson 260. The most impressive data is the nice rpm increase as exhaust restriction is lessened and the nearly equal improvement in thrust that ranges the span of propellers tested.

Although the Hanson 260 opens up the rpm envelope, the engineering of this unique 1.6 gasoline engine still stakes its claim in the 9,000rpm range. And although the approximate 1,000rpm increase in open-port performance that divides the stock and Hanson 260 engines is striking, the tests suggest that most of the "pulling" power still lives in a lower range (good news for you IMAC and fun-fly folks). For you speed demons, just throw on a Hanson tuned pipe and header and go for it; I'm sure the Hanson G-26 will twist the starch out of small-diameter, high-pitched props.

For certain, the modified G-26 substantially opens up the range of propeller choices while providing excellent thrust performance for a gas engine of its size. At 44.9 ounces-minus battery and muffler-I think you'll find this engine extremely accommodating, regardless of your intended use. The choice is yours!