RE: [ihc] Turbo Binder Motors

[Tom Harais <THarais@xxxxxxxxx>]

Steve:

Well now, wait a minute.  If by "efficiency" you mean energy output per unit
of energy input (as in MPG) then I'd have to agree.  But if you mean
volumetric efficiency, then I'd have to disagree.

A turbo normally increases volumetric efficiency on either a diesel or a
spark ignition engine.  The difference is that on the diesel, the turbo
increases the volume of air alone going into the cylinders.  Whereas on a
spark ignition engine, the turbo increases the volume of air AND fuel.  But
the diesel has a much broader range of fuel/air ratios that will function,
compared to the spark ignition engine where the functional fuel/air ratios
can vary only slightly above and below the stoichiometricaly correct one.
Thus, a turbo pumping more air (increased volumetric efficiency) into a
gasoline engine's cylinders creates a proportional need for more fuel as
well for the engine to function.  Hence, more power output (torque/power)
from the turbo boost but no improvement in efficiency measured as conversion
of input energy (fuel) to output energy (torque/power) is realized.  

And that's my perspective! ;-)

Tom H., '76 Traveler