First I would like to start with the simple fact that i am new to scale and gas. The scale aspects i am learning as i build a cockpit here, pilot there etc. and with each build i am getting better and better, weathering and building, you can say, i learn as i go. I AM HAVING to much fun. Now for the down side, i do not know a thing about gas engines. What a maze you guys deal with zenoah here, DA there, a new world from my glows. The help i need is this, I had a great deal on a GP p6e skyhawk and i would like to go gas and desided on a zenoah G-38 a little on the overpower side for this aircraft but thats ok, but i can not seem to find how to figure what 3 blade size would be max for this engine. I would like to come close to scale but that will not be practical but close would be fine. I have seen great props by the solo prop company with great hubs, yet i can not determine size or pitch. Please be aware i do not need a hot rod performance, just standerd flight handling. I Have seen the post on the build and also on the G-38 install on the forum they where great, but no word on three blade with this engine. I once was told that one inch less for each additional blade (example: 22x10 2 blade would then go to a 21x10 3 blade any merit to this formula? Guys thanks ahead for the info and good flying.

18X6 through 20X8 will do fine
send some pics so we can all see

Yes...knocking 1-2" off "total" tends to work decently.

As an example, every G62 I've owned likes the Xoar 23x8 prop. When i went to a 3-blade on my big Pitts, I stuck with the same company (Xoar) and went with a 22x8, which gave me similar performance, SLIGHTLY (< 100) fewer RPM's. A 20x10 gave me nearly exactly the same RPM, but slightly less vertical, as you'd expect.

I've seen similar results converting an OS FS70 to 3-blade, and on a friend's DA-50. Up and down the range, taking 1-2 total inches off the 2-bladed prop (by total, I mean combination of pitch and diameter) seems to produce similar engine performance on a 3-blade.

Thank you guys i will start with a 20-8 (3 blade) on the G38 and go from there. I will start with the cheap 3 blade props to get it right before i fork over the money for the solo prop and hub set up. Tell me is there any other company out there that makes realistic type hubs and props that i could look at besides solo or are they the only game in town. This picture is the set up i am looking for or close to it without having to be sitting at the flight ramp changing props out. I know when i was a kid byron was the only company in town working on a reduction system to swing big props, has everyone since then tried it and failed?

I must be missing something i called solo they said to get to a 3 blade 18 on that engine i would need to pitch it at 4 and that would not work. I found the same info at this chart www.birminghamrcclub.org/props.html so i am i looking at a 16 size prop? There goes prop size or are there any other options.

just to be sure???
20*8 3 blade ?

isnt it too big to G38???

a 15x8 sound more suitable

http://www.horizonhobby.com/Products...ProdID=ZENE38A

check this!

http://www.zenoah.net/products/hobby.../G260PU_EI.pdf
and this one for the g20IE

The prop chart should be viewed as suggestions and not as 'engraved in stone'. Personally I think that your G38 will be quite happy spinning a 18x6 3 blade prop, as it has the ability to turn fairly large props.

Karol

karol thanks i will try an 18x6. Just a thought have you tried this combo at some point? Does these ei units work good on these engines or is there a better set up. Please excuse my novice questions but my future was said to be scale and gas, at least thats what that old lady i payed 50 bucks said to me lol.

No problem here, as questions were made to be asked so ask away. Electronic ignitions are very reliable and work extremely well, and the G38 can be easily converted to EI. The major advantages are ease of starting and a significant weight loss due to the magneto system being dispensed with, however in some scale applications the extra weight can be an asset.

RC Ignitions and CH ignitions would be my first choice for any such conversion. Best of luck in your scale endeavours.

Karol

can you please pot some pics from your local JAMAICA rc filed

http://mickreevesmodels.mysite.wanad...ccessories.htm down the page past the control panel. It's for a G62 though.

Thanks guys for the info, it was great and yes gadix i will post pictures soon. After looking at the web site in England soarrich i see no reason why the unit would not be able to be used in the 38 the drawings on the horizon site shows that size between engines is very little i will drop them an email to see if they had tryed it maybe the crank is wider. i will keep you posted.