Yes, in theory, a lower tuned engine is easier to mod up for more power, but the trade off is that you can start with something already worked up and then add biger and badder extras like a turbo and not have to do the more minor stuff like cams or intake manifold, etc. Efficiancy and fuel economy are not always related. The difference between the HP of the Vet and s2000 is apples and oranges, one has a huge motor (ie: vet) that is undertuned to produce easy hp and gobs of torque while the s2k is highly tuned and must be pushed harder to produce bigger numbers. I don't know if that makes any sense, I'm not quite sure how to word this, maybe one of the smarter people on this board will step in and take over where I left off...