straightnickel,
Check the other recommended comments.
The SIG Banshee was designed in the days of 6 1/4 ounce Fox 35s, w/out mufflers, on light wood props. Most modern engines weigh more, plus the weight of the muffler. (The nose is too long for today's power!)
By the way, the Banshee and Twister use the same basic wing. Both fly well, and can be tweaked to fly better with today's gear. Differences are in the wingtips and fuselage...
Adding weight to balance the modern power systems, and using a tamer engine runs into practical limits on the wing and tail layout. Best advice I see in other posts so far is to move the wing forward, Not simple, but keeps a good relationship with the tail. As long as there's room for a 3.5 or 4 ounce tank, most problems are answered.
It is still a simple profile, so dumping extra power into it is a sort of answer, but not (IMO) optimum. The location of the prop is not a major concern, except as it relates to the weight of the engine and room for the necessary tank. The wing is good - strength, airfoil and structure work. Weight overall is a concern...
{Personally. I don't care for the side view.) That gives you the opportunity to "kit-bash" to something you'd rather see at the other end of the lines. Very little would be needed - different "cockpit", different fin, etc. Just keep the flying surfaces near the original, given that you may move the wing further forward...
Good flier as stock, with a light engine and possibly going to 57.5' lines (eye-to-eye) instead of 60' eye-to-eye. Shouldn't need shorter...
Build light and straight, and don't weigh it down with a heavy finish. You'll enjoy!
Last edited by Lou Crane; 01-19-2017 at 10:42 PM.