Ok, I have posted this a couple of times and haven't had any responses so I will tryi one last time. I am building the Wing MFG B25, I want use gas power for this critter but I am having a hard time settling on something. I would like a bit of input and ideas from some people that may have experience with this aircraft and/or engines. it says its to use 70-90 Four stroke glow so my first thought was one of the those 15GX gas engines from Evolution but I am not liking the lack of info or reviews on it. The few reviews I could find about half or better didn't seem real positive. So, I thought maybe DLE 20's since they are tried and true but wonder if those are TOO big for this aircraft. I am not convinced on the reliability of glow power on a twin however, I am open to suggestions.


Thoughts Please!!

One reason for no responses may be it has been a long long time sense I have seen one of the Wing 25s built. Even when wing was cutting them you only saw them at fly in shows.
If you want to know something about any of the new gas engines then a good place to look would be the gas engine forum. There are a lot of pages written about the new engines, even the gas four strokes.
Wing MFG was not one of the run of the mill kits that most people were building so you won't get a lot of response.

I too have a Wing B25 on the table. (Actually, it's not on the table 'cause I'm hung up on building operating gear doors, but that's another story!) Obviously, it's not been flown. The current plan is to use a pair of Saito 80's. I'm hoping that's enough power. I've run a couple of different Saito 100's with no problems, and seen several other folks at our field reliably run Saito's of various displacements. (And this is not a Saito commercial, I've also used Magnum 4 strokes.) At one point I was dreaming about using a pair of the (apparently now not available) Saito 90 3 cylinder radials. Then I looked at the price...

I have no direct experience with gas engines, but here's what I think FWIW:

(1) A pair of DLE 20's is probably too much power for your Mitchell. I'm guessing it'll come out around 15/16 lbs, and one DLE 20 would probably be able to handle that much weight.
(2) I watched one guy at our field struggle with one of the small Evo gas engines (I think it was the 10cc model). It's operation was spotty, and eventually he found some kind of problem with scoring on the piston. The engine was replaced under warranty, but the new one never seemed to run reliably. At the same time, the LHS guys had positive experiences with the same Evo engine.
(3) I'd be tempted to look at either the OS 10 or 15 cc gas engines.

Whichever route you choose, I'd make sure that each engine is really well broken in, and has been flown for a couple of hours in a single engine set up to establish reliability. If and when you get to the point that engine failure is pretty far down on you list of worries, then it's probably ready to put in the Mitchell.

I,m also building the Wing B-25.I am working on the nacelles.I'm using Saito
FT-90 twins

Hi!
What´s important when building a scale model and certainly more so when building a twin engined airplane is building it light! Light planes always fly better than heavier planes and last longer!
People seem to forget this and use too heavy engines on their planes thinking "I could always throttle down" and that´s a wrong way of doing it!
So...using large heavy petrol engines is no good if you want to keep the plane for any longer time.
Instead use the smallest, lightest engines you can have, but of course with adequate power, and that is why you should use a pair of .70 four strokes and propping them for around 9000-10000rpm (13x6 two blade or 12x6 three blade).

Yea but they don't sound as good.And from far away you can't see the engines. I'm not entering it in any contests

[TABLE="width: 100%"]
[TR]
[TD]wings B25 specs

GENERAL[/TD]
[/TR]
[TR]
[TD="colspan: 2"][/TD]
[/TR]
[TR]
[TD="width: 35%"]Power Class:[/TD]
[TD="width: 100%"]Glow (.40 - .59)[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Class:[/TD]
[TD]Standard[/TD]
[/TR]
[TR]
[TD]Category:[/TD]
[TD]Multi-Engine | Scale | Warbird[/TD]
[/TR]
[TR]
[TD]Flying Skill:[/TD]
[TD]Intermediate[/TD]
[/TR]
[TR]
[TD]Build Type:[/TD]
[TD]Full Build[/TD]
[/TR]
[TR]
[TD="colspan: 2"][/TD]
[/TR]
[TR]
[TD="colspan: 2"]DIMENSIONAL SPECIFICATIONS[/TD]
[/TR]
[TR]
[TD][/TD]
[/TR]
[TR]
[TD]Wingspan:[/TD]
[TD]84.00 inches[/TD]
[/TR]
[TR]
[TD]Wing Area:[/TD]
[TD]920.00 sq. inches[/TD]
[/TR]
[TR]
[TD]Wing Loading:[/TD]
[TD]30 oz./sq.ft.[/TD]
[/TR]
[TR]
[TD]Length:[/TD]
[TD]64.00 inches[/TD]
[/TR]
[TR]
[TD]Weight:[/TD]
[TD]13.50 Lbs.[/TD]
[/TR]
[/TABLE]

I found this info. So 920 sq in of wing and 14 lbs.
In my opinion there is nothing more reliable then a non-bearing two stroke glow. I would choose the OS LA .65 for a twice a year airplane like this.

Small gas is heavy for its power and a new learning curve. 4-strokes are heavy and harder to setup for those two outings a year.

The non-bearing engines store and return to service the easiest. two .65's would hover a 16 lb plane.

Simple, reliable, and powerful. That is my recommendation, no way cool factor or sounds. Just power, simple setup and reliable.

I flew a Hobbico Twin Star for years with two OS LA .25's. Sold it having never crashed it.

Just my opinion on how to go.

Hi!
I agree fully!
Nothing more reliable than those plain bearing OS two stroke engines!

I had O.S. .40's in mine. Darn, i wish i would have kept that plane.

OldScaleGuy
That B25 picture in your gallery of the bomb drop is SUPER!

Thank you! That is a Ziroli 101" version. Dearly loved that plane, lost to a mid-air at the 2004 Scale Masters Championships near Kansas City.

WW,
I saw one of these fly with twin 91 4s and it looked and sounded great with plenty of power.
The DLE 20 would be a good reliable choice also but you'd probably have to chop more of the cowl to get them to fit
I actually have one of these kits NIB if anyone is interested.

Thanks,
paul
[email protected]

.91 four strokes will be too heavy and fly too fast!

Hay Jaka & Kmeyers,
I agree 100% with your comments on your choice of engines. I've several K&B .65 Sporter in models over the years and these had to be on of my most reliable engines I've ever used. I've been in this hobby for 60+ years and found the plain non-bearing K&B engines to not only be very reliable, easy to start, idle so low it amazed me, but never failed me. I've acutally warn out several K&B .65, .28 and 45's over the years. They are solid engines and 1/2 the cost of any bearing engine and the best bank for your buck.

Happy Thanksgiving,
Bobby of Maui

Maybe some of those OS 75AX's.....What's your thought on those. Seems like a good blend. I have an OS 70 Surpass II. I LOVE that little sucker....has well over 300 flights on it with NO dead sticks since it came out of the box. I wish I could find a pair of those. One of the best engines I have ever had in my life. But you can't go wrong with OS. I have heard the people that are having issues with the Evo mini gassers are not tuning them right. Trying to tune them like a glow engine and that just doesn't work. I dunno.