Ted B.
I think you missed the part about me writing engine simulation software in our earlier exchange. If you'd like to discuss the Otto Cycle and what that precisely means and entails, and how it might or might not have any bearing on what you currently believe about engines and fuel economoy, feel free to ask.
If I'm not mistaken, what you're stating is that one can multiply the redline by around 40% and take a look at the speedometer when travelling at that engine speed in top gear. Whatever speed you're running at that point is going to give the optimum fuel mileage, correct? And the reason for this is because of the scientific fact that an Otto Cycle engine attains peak fuel economy at that engine speed (40% of redline). (Note that that figure is most likely referring to engine speed and fuel conversion efficiency, not that in combination with vehicle speed and fuel mileage.)
Consider the consequences of that if it is or were indeed true. This literally means that if you swap out your transmission for a direct drive unit (1:1 ratio), and buttuming your car came stock with a 3:1 differential ratio, your "40% of redline" speed has now tripled. Your optimum speed was 78mph before, which I still maintain is rather coincidentally tied to your 43% value.
With the new driveline unit your optimum fuel mileage now occurs at 234mph if what you're saying is correct. Congratulations, the fuel crisis has now been put off for quite some time. ;-) All we needed were higher gears all along, go figure.
This reminds me of a time in high school when a buddy wanted to put a 2.32 rear end ratio in his Camaro so he could cruise along at 2000rpm in excess of 100mph. Unfortunately he did not realize that the engine did not produce enough power at 2000 rpm to allow that speed to be reached, even at full throttle. But I digress.
Anyway, this should continue to be a fun debate so long as nobody here is the sort of person who would insist his MD was wrong about his "broken leg" diagnosis. ;-)
By the way, the link you posted for your source of information did not work (probably too long and it got abbreviated when looking here through Google). Could you please post it on two lines or with a space half way in between so I can copy-paste it together and view the site?
Thanks, Todd Wbutton Performance Simulations
