Its a clone of the OS40FS of a few years ago same as a royal 40 not a real powerhouse but a good engine It might be the same one I traded about 2 years ago at graves rc towards a saito 56 I got it as a combo offer with a cessna c-37 mail order
I ran it for a while with a davis diesel head (which I still have) but the irvine 40 diesels( have 5) have a little more power
martin