Brudford,

The "Avistar" is one plane, and the "SuperStar" is another.

The Avistar is a semi-symmetrical wing and has a CG of 3-1/4"

The "SuperStar" is a flat-bottom wing and has an adjustable CG (wing shift) from:
• SuperStar 40: 3-3/8" to 3-7/8"
3-3/8" for more docile performance,
3-7/8" is more responsive.
• SuperStar 60: 3-7/8"

Note: The Avistars' CG is designed with a .40 engine in mind. If you change the size, the weight will vari and so will the CG.

Any planes Center of Gravity may be altered by shifting the payload (battery, receiver, servos, fuel, etc.).

The wing design should match closely to the designed CG, so you don't want to tweak it too much or the wing won't work as it should.

That my 2¢ worth.

MacAir