I have a MVVS 26 - same engine - tried it in a H9 1/4 scale Cap 232. It flew the bird but didn't put out enough power to suit me. Flew lots better on the MVVS 35.

One thing to think about: the carb on those engines is awfully close to the prop drive washer. In a Spit, I'll bet the carb will be sticking out, presuming you mean to mount it inverted. I'd use an engine with a rear carb and a thin muffler.

CR