How about a doner engine from a boat. This pic is dressed up for a car the
ox66 must be based on the ox88 from the formular 1 engine. just for the hell of it i am going to research this one.Its tiny and 225hp in normal boat trim
Here is suzukis effort
http://www.hotribs.com/03press/226-suzuki/suzuki.asp
Bob
Edit; that yam weighs 230 lbs is 16.5" long and 21" wide