None of y'all know the REAL meaning of a "huge US car engine". Try my last (and only) car, a 1976 Lincoln Continental
2-door land yacht
with a 7.5L V-8
(460 cubic inches), and a curb weight of just over 6,700 lbs.
It got about six miles to the gallon while I drove it (US$45 or so to fill up the 25-gallon tank, for a paltry 200 mile range), and measured over 19.5' (~6.5m) in length.
For comparison, that V-8 is five times the size of my friend's Ford Escort's engine. But as TallRoo pointed out, the power-to-weight ratio of these two cars is probably quite similar; 385 lb-ft of torque can only do so much to move a gunboat like that old Lincoln. The difference is that in the Escort the engine whines incessantly on its way up to 90mph; in the Lincoln, that big-block purred at 90. Of course, I was scared to take the car past that speed because of the completely shot front suspension alignment, which caused a scary lack of stability anywhere past 65 mph...
At this very moment, my good friend is putting the finishing touches on that engine, newly rebuilt and modified along with its attendant C6 transmission, in order to do a "custom install" into his 1973 Mercury Montego sedan...Update 9/12/01 The transplant is complete...but the stock transmission is severely lacking, and will have to be replaced with a truck unit.