Paul,

Published in the October 2009 issue of Automobile.

Two engine technologies- turbocharging and fuel injection- have recently
joined forces in mechanical matromony.  Spraying the fuel directly
into the combustion chambers achieves more precise mixture control,
since no droplets are left behind on the intake port walls, injecting
the fuel at 2000 or so psi versus the 50 psi common with port injection
facilitates finer atomization and more complete vaporization.  Also
the cooling effect from the fuel's change of state from liquid to vapor
enables significantly higher compression and expansion ratios.  According
to the EPA, the net improvement in efficiency attributable to direct
injection with turbocharging is a substantial 12 %.

Who has it:   BMW,Bugatti, Chevrolet,Ford, Lincoln, Mazda, Mini, Porsche,Volkswagen.



I checked with Mazda in Missoula, MT and they never heard of it.

Gene Sandburg

I'll believe it when I see it/ Direct injection in a gasoline engine is not
easy. They have talked about it for years. Mercedes had direct injector
50 years ago in their race cars. Formula 1 engines would have direct
injection if it did anything and they don't.

Porsche spent big bucks on R&D and the improvement was barely noticeable.
It is also very expensive.

Paul Lamar


Gene,

That is what the 16X is all about.  Look at the injector on top of the
engine. Other locations below the oil injectors.  When injection occurs
the pressure is close to ambient so no need for 2000 psi.  No hard data
available but it stands to reason that the hot rotor would vaporize the
fuel.

Doug in Japan.

The 16X is not direct injection in the truest sense of the word. Injection
occurs early in the compression cycle. It is like those pressure taps
we have screwed into the oil injector holes.

Of course it remains to be seen if it is a real improvement.
I doubt it. Mazda needs to stop screwing around and recover some
of that 50% of a gallon of gas going out the exhaust.


Paul Lamar