On Wed, Jun 11, 2008 at 6:20 PM, Levi Pearson <[EMAIL PROTECTED]> wrote: > An anecdote isn't very useful without some theory to back it up. > That's how quacks sell stuff. If you can give a plausible theory as > to why a turbo would increase the cruise efficiency of a gasoline > vehicle, I'd be interested to hear it.
Sorry, missed part. The theory is rather simple, and you've skirted around it several times. More air means bigger boom. Bigger boom means one of two things. 1-more power on the same amount of fuel, which is normally the case if the Throttle Position Sensor is telling the computer that the pedal is on the floor or close thereto. 2-the same amount of power on less fuel, which is what happens when the TPS is not telling the computer the pedal is on the floor. In this case, a change in the emmissions sampled by the O2 sensor behind the exhaust header tells the computer to send less fuel, because your foot isn't telling it to send more. There are lots of cases where due to the characteristics of an individual type of car or engine, mileage can be influenced by seemingly inconsequential things. In my current car, for example, I noticed on one trip that, much to my surprise, I got better mileage with the AC on than on the same trip under similar conditions without running the AC (just over 3 mpg). So I started tinkering and discovered that the computer advances the timing a little bit when the AC is on. Apparently the characteristics of my current engine are such that the fuel is more burned more completely with the timing advanced than under "normal" conditions. Several subsequent trips proved that this was not an anomaly, so now I leave my AC turned on. Again, this all drives my wife nuts, but the mechanic in me always forces me to figure out what's happening when I observe something out of the ordinary with my car. -- Alex Esplin /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
