It sure looks like it could be an Echo / Kioritz 21.2, but the cooling fins are a bit different than mine.
Here is my engine:
http://www.rcuniverse.com/forum/m_91...tm.htm#9153860

I put an Rcexl ignition on it and it is a super engine. I have it on a 16lb. oldtimer for floating around with. I've tried many props from 13x8 up and am currently using an 18x8. The big prop only turns about 5500, but is more to scale on the plane and pulls it right along. It starts easy and runs so smooth. Here it is landing:
http://www.youtube.com/watch?v=pEDqPsCNk30


http://www.rcuniverse.com/forum/m_82...tm.htm#8228949

Rod S