SonexBuilders.net

Thanks Tony, it's good to know the history.

Further explanation of my choice of prop.
On my first engine, the Jab 2200 early hydraulic lifter engine, I fitted the prop recommended by Sonex, a 54x50 wood/composite coated. I was able to get 3300rpm plus static (ie WOT on the ground stationary), which indicated the engine was not loading up sufficiently for the rings to be bedding in properly. As a result I needed my first top overhaul at about 400hrs and the second one, when it glazed up again, at about 480hrs. It used over 100ml oil per hour!

At the time of my second top overhaul I went to the 54x54 Sensenich wood core/composite covered prop. This gave me 2900 static, which indicated the engine was suitably loaded up. The engine again quickly lost power after the second overhaul and continued to use excessive oil, which led me to scrap it and replace it with the CAMIT 2200.

As indicated in the earlier post, the 54x54 seems well suited to the CAMIT 2200 in the Sonex airframe. When the weather improves I will do some climb performance testing and get back to the forum.

Stuart
Sonex181
Moorabbin, Australia

I have a 2200 #1130 on my Sonex #327. I have 500 hours in 15 yrs and have never opened the engine. I did replace the carb with an aerocarb that I am very happy with. Both coils I replaced after a double failure and a glide into a soybean field. The alternator gave up last year and I have put a rotec system on my plane. I am not really happy with it. I have had to fiddle with it a lot. When I bought it the rectifier was gone and the pulleys didn't line up. I got it working well at the end of last year and have put about 15 hours on it now.
The one problem with the 2200 is that the engine is too light. The c of g is about halfway back empty. When you put 2 180 pound guys in it it is at or past the aft c of g limit.
I am moving my engine 7.5 inches forward to balance the plane like a 3300. I have started the mount and have 2 cowls that I will try to make into 1 good cowl. Onward and upward.

There are a lot of Sonex flying with Jabiru 2200s They do tend toward light on the nose, but the engines are already moved forward on a longer mount than the 3300s. Moving engine, forward another 7-1/2" sounds like a lot. If your Sonex is a Waiex tail dragger, which tend to be a bit heavier in tail, that might explain it, but would double check your weights, measurements and calculations before cutting anything.

David A.

I talked to a gentleman in Florida who put a 2200 in a Onex. He moved the engine 9 inches forward. You take the c og g of a 3300 and a 2200. take any measurement to the firewall for instance say 45 inches multiply both then divide one into the other . for my Sonex its 7.5 inches. I hung the engine on my mount with pipe and ready rod at 4 inches out with the cowl and muffler and prop on. It was not even close to the c of g of a 3300 Sonex.
I have lead (12 lbs) bolted to the cowl as far forward as possible. It helps but it needs roughly 30 pounds for mr to achieve the perfect c of g of the 3300. My 2 cents