ORIGINAL: earlwb
I have this version of the Enya 11 CXDS engine. It appears to be an ABC model.
I'm pretty sure that there's the 2.1 cc, ABC, 11CX-D Ultra, and the earlier 1.8 cc, AAC, 11CX-D. Both are 'Model 2201's. Apart from being less powerful, the 1.8 is a whole lot lighter.