11/12   Anyone can read Japanese here?  The mileage ratings for the Japanese
        Prius range from 27.0km/L to 35.5km/L, which translate to 64mpg to
        84mpg.  The 2007 US EPA rating for city is only 48mpg.  Is the Japanese
        city driving condition really that different?
        http://toyota.jp/prius/ecology
        BTW, what's "10.15 mode" vs. "JC08 mode"?  Thanks.
        \_ Hybrid mileage is a hard thing to measure.  EPA recently had to
           totally change the hybrid rules to make the results more in line
           with real world usage.  Before that the Prius was a lot higher.
        \_ Just a guess: Japanese pollution emmissions are less stringent
           and that leads to an increase in fuel economy.
           \_ Before that the results for non-hybrids cars were a lot higher
              too.
        \_ Just a guess: Japanese pollution emissions are less stringent
           and that leads to an increase in fuel economy.  For example, I
           believe the Subaru WRX was not available in the US for a long
           time because of pollution emissions.
           \_ I follow changes to the Corolla engines (not so much with the
              Prius), and I know that Toyota moved to using direct injection
              in their Japanese engines in 2003, which results in better gas
              mileage.  They can't do this in the US because gasoline in the
              US contains far too much sulfur.  US gasoline content was slated
              \_ What are you talking about? My Lexus uses direct
                 injection and so do a lot of other Toyota cars.
                 \_ That was the reason cited *by Toyota* for not using
                    direct injection *in that engine* *at that time*.
                    Running gasoline with high sulfur content in a lean burn
                    direct injection engine leads to sulfur fouling of the
                    catalytic converter.  You could get around this with a
                    catalytic converter with a much more expensive catalyst
                    or by changing the fuel/air mix.  However, the point
                    holds: this is a concrete example of an engine technology
                    with better mileage in Japan than in the US because of
                    more stringent Japanese environmental regulation.
              to reduce the sulfur content in 2006 (from 300ppm to 30ppm),
              but this was postponed indefinitely under pressure from the oil
              companies.  I'd be surprised if that development wasn't in the
              Prius engine by now.  So yes, environmental restrictions are
              part of the difference in gas mileage between US and Japanese
              Toyota engines, but it's (at least in part) because of *more*
              stringent environmental requirements in Japan.  Incidentally,
              in addition to improving gas mileage, the switch to direct
              injection also increased horsepower and torque in the 2003
              Corolla.
              \_ Cool info. What about Honda Accord engines? Why did they
                 change the engine in 2006/7? It sounds very differently
                 during startup, and revving.
        \_ I wish American car companies put this much engineering effort
           into their products, instead of figuring out how to sell the
           average consumer fucking 100 pound chromed cow ramming barriers
           on the front of their SUVs.  Seriously, who needs that shit?
              \_ Cool info. What about Honda Accord engines? Why did they
                 change the engine in 2006/7? It sounds very differently
                 during startup, and revving.

           \_ Men who haven't had good sex in over 10 years and need to
              overcompensate because otherwise they would have to admit
              that at half of the reason for that is them.  Just ask
              MR Women-don't-like-sex guy.
              \_ Yes, and the other half of the reason is that women don't
                 like sex, which you seem to ignore completely.