[Tigers] Tiger Gas Mileage

[Smit, Theo]

I'll bite: Are diesels actually more thermodynamically efficient than
gasoline engines? It's a rule of thumb that in a typical gasoline
engine, about 1/3 of the chemical energy in the fuel goes out the
tailpipe, 1/3 is dissipated in the cooling system, and 1/3 actually does
useful work in getting the car down the road. A turbocharger helps in
this regard because some (how much?) of the exhaust energy goes into
compressing the intake charge and thereby helps do useful work. But is
there any intrinsic value in using diesel fuel? Diesel has higher energy
content per gallon, which is why you can always get better mpg values
using diesel (and your M85/E85 "mileage" will be significantly worse),
but are the engines actually more efficient?

Theo