Originally Posted by **dereckbc**
Can anyone direct me with a link that covers various plane sizes and motors? No need to cover scale as I get that.

Motors have me real confused like size 10, 15, 25 ect which I think mean equivilent to gas mm size.

Then I see on sites like Hobbyking 32-40 act which seem to be physical dimensions.

Trying to figure out how to upgrade a plane motor for a little more power. For example I have a plane with a EF 15-BL, and I think I can use a 25 BL from Heads Up RC, but not certain. What it boils down to I do not know what I am looking for and with hundreds of motor out there is very confusing.

Plane sizes also has me a bit confused. For example a 300 or 400 size. I know that is some measurement but what?

Question:

What size model, weight model, and power system are you interested in?

Electric power can vary from little tiny models that fly on 20 Watts or so, to the 3000 Watts I'm running on my giant Big Stick model.

There are a number of very good computer programs out there. The one I use is

www.motocalc.com, free for 30 days, then $39. This and similar type programs are only as good as the specs on the motors provided by the mfg. Some of those specs are not worth the paper they are written on.

What will work out fairly well is the number of watts per pound of airplane. Around 90-100 watts per pound will perform well on most model types. And, 150 Watts per pound will be an excellent performing model.