Eastern,

You may want to re-evaluate your plans. I have an Early FEJ F-16 with a Wren SS (same weight as a 54). I debated the pros and cons of tail vs. mid mounting the engine. After weighing all the components and calculating moments for both scenarios I concluded that after balancing there was no weight advantage to tail mounting it.

Unless you don't already have a pipe why not conventionally mount the engine? I had to add 24 oz. of batteries to the nose to balance mine. I wouldn't have gone with redundant batteries if I didn't need the nose weight. Additional nose weight would be required for a tail mounting.

By the way mine came out to 20.5 lbs. dry and I wish it had more power. I don't think it would perform very well with only 14 # of thrust.

Joe