On Wed, 22 Aug 2007 14:01:49 -0500, lid wrote:

The "blower" just provides the normal air pressure required to run the
engine (other 2 stroke designs do the same thing with crankcase
vacuum/pressure). But a "supercharger" would provide more than that.
An extra (super) boost so to speak. Thus the use of separate
terminology. Izat about right?

Almost. Superchargers and turbochargers both generate boost pressure,
the difference is in how they are driven. Superchargers are direct
drive (belts, gears, etc), turbos are driven by exhaust pressure.

PhantMan wrote:
The "blower" just provides the normal air pressure required to run the
engine (other 2 stroke designs do the same thing with crankcase
vacuum/pressure). But a "supercharger" would provide more than that.
An extra (super) boost so to speak. Thus the use of separate
terminology. Izat about right?

Wayne.B:
Almost. Superchargers and turbochargers both generate boost pressure,
the difference is in how they are driven. Superchargers are direct
drive (belts, gears, etc), turbos are driven by exhaust pressure.

Right. Which is why I was confusing the "blower" term with a
"supercharger" rather than "turbocharger", since the blower is not
exhaust driven.
My ambiguous message up there was referring to the reason the DD
blower can be considered part of a "natually aspirated" system rather
than supercharged.
I somehow don't think I'm making sense today.

Rick