I don't think the LS7 is all *that* much smaller or lighter than the Ferrari V8. If the specs are to believed, it's the Ferrari V8 that is noticeably lighter. They make pretty compact V8's too (though the LS7 probably has a lower CoG). Adenauer: That's only ONE way to measure efficiency. Unless you live in a country with displacement taxes, hp/l is a fairly useless barometer of efficiency, in terms of real-world results. An S2000 (now over half a decade old) makes more hp/l than the Ferrari V8. It is more "efficient" than the engine in an Enzo. Would you really want that kind of engine powering your Ferrari? Because of the real-world results and benefits? How about a motorcycle engine (160+ bhp/l), or an R/C car engine (~400 bhp/l)? Someone else could very well suggest that efficiency can be measured by manpower hours involved in making an engine (or materials used, etc), compared to its output... I don't see anything wrong with someone eating a Whopper with a glass of chianti. It's great to have that choice (even if it's not my personal preference).