Fuel injection plugs

[James Ballenger]

Howard Wilkinson wrote:

> James:
>     I didn't say that very well..... What I meant to say was that due
> to fuel charge stratification the area in which the spark plug is
> located where combustion is initiated is at normal ratio, but the
> surrounding area may be extremely lean.

That makes more sense, thanks for clearing it up.

>     The ideal engine (in terms of efficiency) is like a diesel where
> power output is controlled by fuel supplied not by air fuel mixture
> being supplied under a vacuum (throttling) which results in lower max
> pressure prior combustion.  Basic thermodynamic theory shows that for
> a given amount of thermal energy the pressures will be higher if a
> full charge of air is available for expansion.  We are after all
> developing power from the pressure, so any way we can achieve more
> pressure from a given amount of fuel will improve our efficiency.

Doesn't greater effeciency tend to indicate, at least, a potential for
greater max power output?  All else being equal, if the system was setup
for performance it would do so more easily than an mpi system?

>     My comments on 4 cycle direct injection were not relating to the
> Orbital system.  It's been awhile since I chased this info down on the
> web.  I believe Mitsubishi or some other Japanese company is at the
> forefront of direct injection 4 cycle engines and may actually have a
> car on the market by now.  This type of system was the one I described
> with the two injectors, one being direct, and one port.  I believe
> they are using the same basic Siemens type injector as is used by
> Orbital, and info on these developments is probably to be found from
> the Siemens web site.  Try the link below... I'm not sure if it's
> current.
> http://www.frostbyte.com/siemens/siemens/powertrain/

It's a dead link.  I have seen a few direct injection designs in car mags
from chrysler, probably in cooperation with mitsubishi, that are
interesting.

James Ballenger