Mike, thanks for the kind words. Never flew a Dirty Birdi but have flown several Mach 1's. I have to tell you and couple SPA members will agree with me. A 7 lbs Daddy Rabbit with an OS 91 (4 stroker) will make a believer out of you. I don't think it rolls as well as a Mach I or the (2 stroke) Kirkland A6 I had. The trade off - in my eyes - is you give up a little on the rolls and gain a whole bunch everywhere else. It's definitely a keeper.

Remember the early 70's, before tuned pipes or mufflers, when pattern planes used only an exhaust baffle for idle. My guess is the pictured rabbit is every bit as fast as a Webra (Blackhead) powered Mach 1. Difference is with the 4 stroke I can make the airplane really tiny at the top of "Figure M's". You get better scores when the Judges see a smaller plane. <grin>

In case you haven't figured it out, I love vintage pattern designs; Not vintage equipment. There is no way I'd have anything to do with the old radios, retracts or engines. With one exception: I'd sure like to have a set of metal open face Proline Gimbals in my Futaba.