Guys, I thought i will add my two cents worth..I think I have heard every type combination possible,here, on what to use on a FJ! I have tried the Medusa V-2 motor, (as REP suggested)....to no real avail! I bit the bullet, and put a Mega 16/15/2/ with an APC 5.7x3 prop, and 3300 3S lipo...Now, This plane goes vertical, as fast as it goes in a power fly by! Radar is about 130mph! I tried an APC 4.75x4.75 also, and it hauls a.. in a power dive, but does not have the vertical "pull" that the 5.7x3 has. (the 4.75x4.75sounds bad as hell though, rpm wise)...I am drawing about 73 amps on full throtle, but the 54 amp thunderbird seems to handle it with no problem! My friend also has a FJ with a mega 16/15/2, and his is ballistic on APC 5.7x3...I'm going to experiment with more props.
I think that is the key, as i truly think I have the right motor! Thisw bird is FAST!!! Paul