ORIGINAL: overbored77
ORIGINAL: Insanemoondoggie
Welcome to RCU , glad you made it back to the world of RC
I have this plane, and have had a ST.40 , Evo .46 and a Magnum 4 stroke .52 in it . The 4 stroke is what I`ve stuck with and my second choice would be the ST.40
The 2 strokes work fine ,but do not have the same pulling power as the 4 stroke. The plane just handles better . No need for speed , it`s a trainer.
For a 2 stroke , the O.S .46 is the easiest motor I`ve ever dealt with., but if you are confident with your tuning skills , don`t be afraid of the lower end engines . Once broke in and tuned they run just as will as an O.S and most have more power.
I make this recommendation based on fact , not personal preference . Let the beatings began.
This is not meant as an attack on you, or your skills tuning and your many years of experience in this hobby.
Just a question as to what type of Dyno you used to do a comparison test of the lower end engines VS OS.
and do you have copies of the test results.
Well, Insanemoondoggie did say to "Let the beatings began (sp)."
The good news is, overbored77, that you don't need to use a dyno to measure the relative "power" of an RC airplane engine. RC airplane engines are designed to do one thing and one thing only, they're designed to spin a propeller. A propeller is designed to push (or pull) air, and the faster a propeller is spun, the more air it moves.
You can compare the relative power output of two similar engines simply by running them with the same glow plug, the same fuel, and having them spin the same propeller. The one that spins the propeller the fastest is the most powerful. A Glo Bee tachometer from Tower Hobbies costs $24.99 and will allow you to make accurate comparisons between different brands of engines. There are plenty of folks in the Glow Engines forums who do this all the time and then post their results:
http://www.rcuniverse.com/forum/forumid_173/tt.htm
There are certainly other considerations when choosing an engine such as warranty coverage and quality of service, availability of spare parts, fuel requirements, ease of tuning, ease of break-in, aestethic qualities, and expected longevity just to name a few.
Insanemoondoggie's assertion that many less expensive engines will out-turn a comparable O.S. Max engine can be confirmed easily enough simply by viewing the Tachometer Readings forum to which I provided the above link. Still, the question isn't so simply as dividing peak RPMs by the selling price of the engine. O.S. Engines are highly prized for their many fine qualities even if they don't turn a prop any faster than a GMS or Super Tigre engine of the same displacement.
As for the original poster, I hope I gave RBachman some food for thought. I think he'll enjoy flying his Kadet with a 4-stroke on the nose and he doesn't have to spend a small fortune to do so. Let us know what you decide on, won't you?