Mine is a Great Planes 60 size.

Length: 60" [1,524mm]
Weight: 10.25 lbs [4,592g]
Wingspan: 71" [1,803.4mm]
Wing Area: 1360 sq in [8,840 sq cm]
Wing Loading: 17.35 oz/sq ft [485.5 g/sq cm]
Radio: 4-ch (5 servos)
Engine: .61 two-stroke, .91 four-stroke [10cc 2-stroke, 15cc 4-stroke]

The basic rule is 1200 sq. in. for a weed eater motor and mine flys great with the Toro.

A friend is building the SE5a kit from Dyna Flight and were planing on using the 25cc poulan in it.
It actually has shorter wings than my Tiger Moth.
The Cowl is very narrow so the rear Carb and Exhaust is a perfect fit.

I hope the Poulan performs as well as my Toro does.