Quote:
Originally Posted by Christ
My point was that car makers are spouting off that engine efficiency has gone up considerably over the last 20 years.
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To some degree, it has.... Which is how less aerodynamic cars than mine produce more power with better FE number (grrrr).... There's room for improvement - for a CR ratio of 10, the theoretical max is circa 60% for an otto cycle... Realistically, we're falling around 25/30% or so.
Otto Cycle -- from Eric Weisstein's World of Physics
MetroMPG has a picture posted somewhere showing weight dependent mpg versus year.
It's important not to confuse mpg with thermal efficiency
