Today I was able to use my AP.061 on my Corehouse Lil Hacker. I had an adapter made for the case to accept a Tee Dee venturi. Initially I wasn't expecting the rpm's I was getting today. The adapter is quite simple and is held in by a press fit and the two screws that were holding the stock r/c carb in. Set screws from wheel collars were used in their place. This just meant the case had to be tapped to that size. This is pretty neat because I can use this engine for combat and stunt just by a simple switch of venturi and needle valve. For combat today I used a Ace needle assembly  128 threads per inch needle with the Cox venturi drilled out to 1/8th. Using a APC 4.5x3.5 prop I was getting 25K plus. My launch rpm was 21,750. The engine was still crackling a little rich but plenty of power. I'm surprised how much power this engine is making. Using the same prop and stock r/c carb my tests resulted in only 23k. This is using the stock plug and 2 head shims on 10% Powermaster. I'm pretty confident a Galbreath setup would even increase the numbers a bit as well. I'm pretty pleased with these figures. I've been playing with other wings and engines to get a well running matched pair that's inexpensive to use. I think the plane fits the bill perfectly as well as these engines. Ken

                 Hi Dan, one of our club members Dan Banjock made it for me last week. Dan is a top notch stunt flyer and builder. He makes lots of parts for older engines when he can find the time. He has been a tremendous help to all of our members. I certainly didn't expect these kind of rpm numbers. I hope the engine will maintain longevity. I'm not a big fan of the Chinese products but I really hope this one works out. I will try and get my son to post some pictures of this adapter. Larry Renger actually explained it to me via e-mail and I took it from there. I explained to Dan that I want to be able to switch the venturi and needle assbly's back and forth so if I want to fly stunt I can. The adapter was made high enough so that you could use a Kirn Kraft unit on it if need be. You own some of these and you can see how they're longer than the stock Cox unit. The Cox venturi is a 1/4x32 thread (same as glow plug) and he drilled and tapped some quality aluminum then turned it on the lathe for a nice press fit into the case utilizing the stock o-ring. I was using a Norvel AME .049 on the Hacker prior to this engine. There is a significant difference in power between the two engines. I have a lot more speed with the.061 and this plane needs it. The Hacker has a fairly thick wing and needs to be built as light as possible. I did this by symetrically placing cored holes through the wing  and routing out some of the solid ply parts. These planes were designed to balance with the Cox reedies and integral tank. This places the nose weight way out front. Using the beam mounted engines you need to be creative to get the plane to balance correctly. Mine required almost 3/4 oz directly behind the firewall. Phil suggests to cut the stab down which will move the cg forward as well. I will try this on my next build. I just want to be able to replace a plane or engine without breaking the bank. This combo so far seems to be effective. I will save the good stuff for later as we gain more experience. Ken