You don't say what brand your 40 size bipe is, but this particular msg thread is on the
Great Planes Ultimate 1.60 ARF.
You'd do better to post about your plane & search for other similar postings in the RC Airplanes msg section.
http://www.rcuniverse.com/forum/forumid_226/tt.htm
As for your engine, head over to the Gas Engines msg section for help on that.....
http://www.rcuniverse.com/forum/foru...smode_1/tt.htm
Hope that helps ya!