If you want the ultimate Microcar, then get a Fisher Fury. Shove a Hayabusa motorcycle engine in it(as is very common), and you'd have what is basically a motorcycle on wheels with better aero. 0-60 in ~3.5 seconds, 50+ mpg, 160+ mph top speed, 900 pounds curb weight, corners almost like a Formula race car...
Neato. Looks front engined though. (Do you know if it is?) I've decided that my toy car should be mid-engined.
It looks mid engined in the sense that the engine is abaft the front axle. If the necessary dynamics are that a centralized mass gives it a very low moment of inertia, then it may work. Maybe.
It looks like it's rear-driver though.
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Reality is merely an illusion, albeit a very persistent one. - Albert Einstein
Personally, I think shoving a 1.3L 112 horsepower CDTI Opel diesel into one would be great. Run that ****er on B100, and you'd have a 0-60 mph in < 5 second, 100+ mpg rocket...
Or there's always the ethanol version with a baby V8, or maybe a Li Ion battery conversion with 150 kW AC Propulsion drive.