Mitsu MDI

[Frederic Breitwieser]

>economy but not really power, I think. Does anyone know the mechanics of
>the Mitsubishi GDI(gasoline direct injection)series engines combine
>incredible 
>economy and power? 

Hey Ross,

A recent article in Turbo and High-Tech Performance explained how the new
GDI (not MDI like in my subject header <Grin>) works, and seemingly, it
works very well both from a performance standpoint as well as emissions.  I
can post some of the supporting text when I get home to the magazine if
anyone wants...  Its a long-ass article, probably way to long for this list.

But in a nutshell - they run the engine extremely lean (40:1 - 50:1
air-fuel) during idle and cruise, with all sorts of neat gizmos to manage
that.  At WOT, obviously it comes down to the normal 12:1 range.

By injecting the fuel directly into the cylinder, the system shoves the
little bit of fuel (in lean mode) right in front of the spark plug, so
immediately in front of the spark, its not overly lean, but rather close to
a stioch mixture (14-15:1 or so).  The rest of the air in the cylinder is
not really part of the combustion process, but more of a "air cushion"
surrounding the explosion.

My analogies are horrible, I know.


Frederic Breitwieser
Bridgeport, CT 06606
http://www.xephic.dynip.com/

1993 Supercharged Lincoln Continental
1989 4-Door Softtop Humvee (Hummer)
2000 Buick GTP (Mid-engine track car)

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