RE: Four engine model
Hay Bob.
Nice looking plane.
My one weights 4800 grams - a few heavy as your one.
Engines are Magnum 30 four strokes.
Mine is combined old F3A plane, 60 size(modified fus and fin+rudder) and GP Extra 60 (wing -enlarged span on one section, each side).
I had to spend last Sunday to setup engines and engine's servos.
There were a lot of spectacular on maiden fly.