VIRGINIA MODEL BUILDERS

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Being new to the world of Electric powered aircraft, I am looking for a chart that shows the equivalent size of electric motors to replace a gas or glow engine.
Any help would be appreciated.

Dr Kiwi

One useful rule of thumb for diesel or glow 2-stroke motors is: watts = cubic inches x 2000

Thus a .15 = 300W, a .40 = 800W etc

NikolayTT

Also one should take care for the weight.

Flypaper 2

There is a new series of motors on HK where the motor numbers represent the equivalent glow motors.

fanackapan

For those new to electric flight, this is the first question they ask - and there is, unfortunately, no simple answer . Dr Kiwi's rough rule is good. Because electric motors can handle such a wide range of power inputs (current X volts), it is difficult to chart equivalent i/c motors. I tend to work backwards - guess a prop size (does it look right in relation to tha aircraft size), decide on the thrust required - 1:1, 0.75 X predicted flying weight etc) and use an online calculator to get the thrust and RPM. Having the RPM means I can go to motor vendors and ask them to recommend a motor which will turn my chosen prop at that RPM, and with a reasonable currrent draw.

Maybe a simpler way is to use the rule of thumb that for reasonable aerobatic performance, we want over 100 watts input power per lb. of flying wt. 70w/lb for good performance, and maybe 50W/lb for modest performance - and then go to the motor vendor.

The process is iterative, but experience will "give you a feel" for the right motor / prop combination.

Sorry to be a bit long winded, but it's a learning process all E/flyer newbies have to go through

aeajr

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Everything you want to know about electric flight
http://www.rcuniverse.com/forum/m_7100376/tm.htm

This e-book has a chapter on sizing electric motors. 

Some MFG provide charts for their motors, but the correct approach is to size by watts/pound and forget the glow motors.