RC Aircraft Motor selection chart ?

I have been goggling for hours; but, can't find a good site that will help me make comparisons of electric motor sizes and wattage against 020. 025. 046 engines.
This is not top secret stuff; so there must be someplace that helps one select an adequate sized motor.
TIA
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Try http://www.e-fliterc.com /. This is the only outfit that seems to correlate motors with wet engines.
OS
wrote:

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Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:

A "BALL PARK" figure would be 100 watts of motor per pound.
I have found this works reasonably well for converting 40 size planes to electric outrunner power.
For instance: The manufacturer states that the dry weight of the plane is 5 - 5.5 lbs. A 500 - 600 watt outrunner, using lipos, will give equal (sometimes better )performance to a 40 - 46 engine in the plane.
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The April 2007 edition of Tower Talk, the Tower Hobbies monthly catalog, has a really good electric motor guide on page 10 for its Ammo and Rimfire brushless motors that matches a complete power set to the equivelant glow or standard power system.
The chart includes motor, ESC, prop adapter, motor mount, propeller, and recommended minimum LiPo size.
You can look up a brushless replacement for a typical Speed 370 electric motor, a high performance upgrade for a Speed 400 electric motor, a glow conversion setup for a .46 2-stroke, or a glow conversion setup for a .91 4-stroke.
What was eye opening to me was comparing the price of a brushless power setup versus a comparable 4-stroke glow setup. I paid $225 for my Saito .72 engine, and the cost of a Rimfire 42-60-480 outrunner and Silver Series 60A ESC is only $179.99 for the pair. If I can find somebody who's giving away 6S 3200mah LiPo packs, I could save $45!!!
I would hope Great Planes or Tower Hobbies would publish this wonderful chart online somewhere, but I hadn't seen it until I was flipping through the Tower Talk Catalog.
Great Planes does have an online recommendation tool that is kind of handy at their website. You punch in the weight and flying style (trainer, sport, scale, 3D) of the model and the web application will provide you with a recommended setup.

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Ed Paasch wrote:

Well factor in that you could share that pack between two or more planes, and also that there is no fuel cost..and do the sums..oh..and remember to subtract the throttle servo from the cost.
How much DOES fuel cost and how much does a .72 burn per minute?
You should get around at least 30-40 hours total flying time off a pack..maybe as much as 100 hours.
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Ed,
Any chance you can scan page 10. I somehow missed that copy, or have not received it yet here in the swamp. Let me know back channel if you can send it to me.
Red S.

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Hi Troops, You may go here to order the April (current) catalogue http://www2.towerhobbies.com/cgi-bin/wtm001pt Or you can bring up the PDF file by going to the Tower Hobbies home page (www.towerhobbies.com) and scrolling down (left frame) until you see "Catalogues." Under "Airplane Flyer" click on "view online." It's a PDF file so you need Adobe Reader or anything else that will allow you to view PDF files. I haven't checked it out but Great Planes has some comparisons here; http://tinyurl.com/39n43q Good luck!

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Ed Forsythe's links were good ones. The bulk of the glow conversion chart is actually right here:
http://www.electrifly.com/powersystem/glow-to-brushless.html
The Tower verison simply provides pricing next to all of the components that are listed for the power system.
I scanned my copy of Tower Talk and e-mailed Red a copy of page 10.

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Red Scholefield,
If Ed can't scan page #10, I can if you send me your email address.
Earl Scherzinger 'AMA' #40329
Red Scholefield wrote:

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