If you want a less expensive engine, you might want to try Supertigre engines. [link]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXFV72&P=SM[/link] or even less expensive, [link]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXFV71&P=SM[/link] . Either of these will work. They don't have quite as much power as some of the other engines, but the price is good and they do produce enough for your application. You aren't likely to find anything less expensive unless you buy secondhand, which is usually a viable alternative.