Identify this vintage engine?
 

I have a few vintage engines, but this has no markings. Does anyone know what it could possibly be?

Seems to be sized like a .25 and has a champion VG 2 plug?


http://www.rcuniverse.com/forum/atta...mentid=2156089
http://www.rcuniverse.com/forum/atta...mentid=2156090
http://www.rcuniverse.com/forum/atta...mentid=2156091
http://www.rcuniverse.com/forum/atta...mentid=2156092

Early Fox Stunt, not sure if a .29 or .35.

Thank you sport pilot. Looks like you are correct. From what the internet says perhaps late 1940's?

Do not let a Fox fanatic see that engine or they will be all over you for it. It is about a 1949/50 or so Fox and it is probably the Fox 35 and it seems to be in decent shape. The 4 bolt head and 2 bolt back plate and tapered thrust plate are a give away to its early vintage. The heads had a habit of leaking or warping and the 2 bolt back plate also had problems. They were replaced by a conventional 6 bolt head and a 3 bolt back plate. Reinforcement webbing on the front of the case came in spurts over the following years. Shame your missing the original needle valve it might have been an Austin craft but I'm not an expert on Fox engines

As for the plug...Champion was the top rated plug in my area until the mid/late fifties when Champion stopped making them because it cost more to make a glow plug than a spark plug for a car. People started hoarding them for awhile, but soon other plugs were just as good. I still have a few of the VG-3 (short) plugs.

George