I have the Matt Capman ARF that I want to put a Magnum XL52 on. I'm not sure if this engine will be strong enough to really perform as expect. Do you think I should upgrade it to the Magnum 70 or 91? Also I have an old O.S. 91 sitting on the shelf collecting dust, but that may be to big for this plane.

Thanks,

I have this airplane and power it with an O.S. FX 61 with an APC 12/6and the performance is excellent!! I think you will not get the full potential from this aircraft with a 52 size 4 stroke engine, If you have to use a four stroker in it , I would most definetly put the O.S.91 in it. However you might have a problem with prop clearance. I use 14/6's on my O.S. 91 4 strokes. I believe it says you can use up to an 80 size 4 stroker in that airframe so the 91 isnt to far a stretch. I would say go withthe O.S. 91.All my Nitro engines are O.S.I will never stray from the best. You will love that plane, it flies GREAT!!!! Rotten out!!

I'm guessing that's a .40 size plane? I have that engine and while it's reliable, it doesn't make the horsepower that a comparable Saito or OS does. I'd say its comparable to a bushing .40, but of course turning a bigger prop with less RPM. If you plan to putt around scalelike and don't intend to pull vertical uplines more than about 20 feet, the .52 Magnum will be fine. But if you want to fly the plane like one would expect an airshow performer to do, go up to a .60-.70 4 stroke.

Thanks for the input I just wasn't sure about the 52 four stroke. I think I'll go with a .60 that I have in my trainer.

I have mine in a H9 Cub. It replaced an Evolution .46NT, so I can make a pretty fair comparison. With the .46 2 stroke, the plane wasn't over powered but it was comfortably powered. I could fly in mild wind without fighting too much or getting worried about stalling in turns and such, but it still flew Cublike at full throttle. I'd say top speed wasn't over 40 mph. Switching to the .52 Magnum, the plane is underpowered very much like a true full scale Cub was. I dasn't fly it in wind that makes the leaves move more than just a little on the trees, and it stays full throttle for the entire flight. I can pull a small loop and can do a roll and a very short stall turn, but vertical performance is pretty much just whatever inertia the plane has before I pull up. Even gaining altitude can be a little stressful, because it can't hold more than just a few degrees of climb without slowing the plane and getting me close to stalling. I am still breaking in the engine (have about 1/2 a gallon through it) so I hope the power improves a little as the ring seats, but I don't expect much. I enjoy the challenge of flying the plane like that, and I like the sound and the long flight times that are possible. But if I wanted this plane to perform even basic aerobatics I would need to move up to a .65 or .70.

The 52 will not do the plane justice. As for 4 cycle engines, the golden rule is one and a half times a 2 cycle. For example, if the plane needs a 40 2 cycle, it would need at least a 60 4 cycle. Good Luck, Dave