I've decided that my engine probably still wont cut it. I've cut weight as much as I can but I had no basis for why? So I've rigged up a little test using the mounting holes on the bottom of the crazy flie. I've attached thread to this on the bottom (out of the way of the spinning things) and then to a linkage and tonight I will attempt to see which size watchmakers screwdriver it can lift......I may not have a working crazyFlie in the morning!