Hey Paul,

Would the oil injection hole just happen to be in the right spot, in
relation to the rotor cycle phase, to serve as a good spot to install a fuel
injector for direct injection of fuel into the combustion chamber?
  Is that spot subject to high temperatures?

If the injector was located there could the fuel be injected close enough to
the leading edge of the combustion chamber to mix well with the incoming air
charge?  It wouldn't be good if all the fuel was concentrated at the
trailing edge of the combustion chamber.

  Mark LaPierre

Most direct injection attempts have shown no advantage.
Best to put the injectors at the start of the runner so the fuel has time to
evaporate.

Perhaps with much higher pressure injectors on the order of 1000 psi.

Those holes are  great for monitoring the actual  manifold pressure.
They give a consistent number regardless of the typ of intake manifold used.
If everybody used those holes it would be much easier to tune Tracy's EFI.

Paul Lamar
--

  The pictures of the direct injected Mazdas show the injector right on top.
  Murry


True but nobody other than Mazda has driven one yet.
The picture on the web site is of a prototype.

We also don't know the timing or pressure of the injection.
Obviously the pressure in that chamber is rapidly increasing.

Everybody is welcome to try but you will need a lot more pressure than 50
psi. Note there are no direct injection gasoline engines on the market at
this time as far as I know.
Porsche among many others have done a lot of research on the subject
spending millions.


Paul Lamar


We have DFI engines running in the labs here in Dearborn. Soon to be seen at
a dealer near you. We are also spending millions on this technology. Not to
give away any trade secrets, but Paul is on track with his comments. As of
yet, I haven't heard anyone nail the key technolgy that makes it work.
C. Smith

Here are a few more pictures from Oxford. Robin took these and she targeted
the good looking engineer rather than the screen :)

Paul Lamar


Paul


 According to Wikipedia, in 2004 the Isuzu Axiom came standard with what
Isuzu called GDI (gasoline direct injection) and sold in their main stream
American vehicle.

Tom


Where is it now?

Paul Lamar

I imagine a lot of cross contamination between GM and Isuzu..  ;)

Come on Paul, we've talked about this a number of times..  There are
lots of GDI cars out in the field today..  Many of GM's Ecotec engines
are - even before the Government Bailout.  Or maybe that explains why
they needed it.  ;)

Buick, Saturn, Pontiac, Saab, Chevrolet (which are arguably all the
same) have been running these since 2007.

From Wikipedia on the LK Ecotec:

"The camshaft-driven direct injection systems pressurizes the fuel to
52 bar (750 psi) at idle, and up to 155 bar (2,250 psi) at wide-open
throttle."

http://en.wikipedia.org/wiki/GM_Family_II_engine



Matt-

Name one car that uses it now and let me look it up on google.
It ended in 1990.

GM EcoTec? I thought that was Ford.

Paul Lamar


Buick Regal..  Chevy Equinox.  In production.


Matt-

I stand corrected. 30 MPG highway for the Regal is no big deal.
Other cars do as well without expensive direct injection.
http://www.buick.com/regal/features-specs/equipment.html


Paul Lamar