It depends on what mods you've made on your Falcon. if you beefed up and supported the tails... Glassed the wings... and suported the engine mount... then run it at 100n. I have a buddy who runs one at full power with a JC Rabbit... and it is FAST !!!!!!
BUT... if you want to take it down to 18#'s... I would say to take off 9K ~ 10K rpm's up top.