bob8619

Ok the time is near for my new P-47D-1 to get its powerplant. I pretty much narrowed it down to either an FG-21 or an FA-125.

Besides the fuel costs, what will be gained by going with the gas? I have been hearing stuff about gassers tearing up servos and junk.

jetmech05

This is the 60 sized sized P-47 that you were asking about servos right? a 20CC is twice the power plant called for. If you want power and speed and a good sound go with a 4 stroker using cool power 15% 2 stroke fuel. not as cheap as gas but the 4 stroker wont tear the wings off

bob8619

Yeah same plane, I have posts everywhere about this darn thing haha.

alan0899

G'day Mate,
I have an FG21 in my Spacewalker, this engine runs sweet, cheap to run, easy to tune, love it, I also have a FA 125 that was bought for the Spacewalker, it's still in the box.
I get about 30 minutes run time from 10ozs of fuel, & still have some left in the tank, try that with a glow fourstroke. I run a 17x6, or a 16x8.
No problems with servo's, the only time you have trouble with servos is if the engine is way to big for the plane, & the prop is not balanced, blades & hub.
Anyway that's what I think about the Saito FG21.

bob8619

I can get a new in box FA-125 for under $300 vs the FG21 is $504 plus whatever a battery costs. The price difference could buy me about 17 gallons of glow fuel at my LHS. Eventually of course it would save money buying 21. Not looking for the fastest or most powerful, just want a well powered plane.

bob8619

Oh and jetmech, as I understand it, the gassers are less powerful than glow right? So wouldnt the FA125 be more likely to tear the wings off than the FG21?

Rudolph Hart

Only if you ain't flyin it right..

jetmech05

Gassers are not hurting for power....a 20 CC by the math is equal to a 120 2 stroke glow. Twice the engine recommended. While a 125 is a 4 stroker it's power out put would be somewhere around a 90 2 stroke glow. I would go with the 125 for power and I bet it'll fit under the cowl better

BarracudaHockey

My Feedback: (11)

Gassers make power with every cycle, 4 strokes with every other.

As for vibration, any large single cylinder engine is going to vibrate, doesn't matter what fuel type.

WI53072

Yeah the only thing I hate about glow powered engines is the clean-up. Gasoline powered planes are typically cleaner, but vibrate considerably more in many instances. It comes down to personal preference. This is an expensive hobby and the most bang for your buck is an appealing selling profile for me. If I can live with the DLE and afford say better servo's or retracts or whatever, then I am down with it. And after all, does a 4 stroke really sound like a radial anyway? Only a radial sounds like a radial. So now we are talking a MOKI? OMG!! It really is a personal preference it is the modelers choice.

bob8619

Its not about whether it sounds like a radial or not, I'm after anything that doesnt sound like a 2 stroke. I HAAAATE the sound of 2 stroke no matter what it is. Chainsaw, dirt bike, weed whacker, rc.