My Extra weighed in at 8.2 with everything minus engine prop and spinner. The final weight was 12.6 with an OS 160 so some (phantom) weight will creep in but not alot. Also don't be surprised if some of those guys chime in and tell you your scales are wrong that is what they did to me. Be sure and I can't stress this enough go over all the glue joints alot of guys are having the throttle servo tray and other locations come loose! The bottom of my motor box came loose in flight with my fuel tank attached by velcro tearing the fuel lines and resulting in a bad dead stick landing. I hope this helps you out GOOD LUCK!