I have Chihuahua plans and have thought about building one. A TD 09 is a Gonzo engine, and I don't think any usual 09 size diesel is more powerful. I've seen a PAW 09 twin ball bearing competition special run and it is in the ballpark, as is the Cipolla 09. If you pay big bucks for one of the speciality 1/2A combat or racing diesels (1/2A in a lot of the world is 09) you could well have a more powerful motor. The TD 09 is. after all, a 60's era engine.

I've flown a TD 09 in Classic Stunt in a Shark 15 profile, and a Jr Flitestreak. Cox grey 7 x 3.5 prop, 10% Sig Champion fuel, 20% oil 50/50 mix, TD glow head, crankcase pressure off the backplate through a one-way valve to a uniflow 2.5 oz tank. 57 Ft. 012 lines. Turn it loose at about 14, 500-15,000 and get 4.1 - 4.2 second laps.

I'm presently building one of Walter Umland's Shark 15 kits; setting it up with aluminum mounting plates where I can run either a TD or Cipolla 09 diesel. I'm also going to try a Medallion 09 on shorter lines. A friend has a LA 10 with a TD 09 venturi setup on a Jr. Flitestreak which flies quite nicely on 45 ft lines. That LA 10 is really quiet in contrast to the unmuffled TD which is pretty loud.

Jim