Paul

You mentioned you are having a problem with over richness at idle,
reading back through the different postings you didn't say if you were
using Tracy's 2/4 injector method or if you are trying to turn down 4
fire hoses so to speak.  I just thought I would throw this on the table
as sometimes it's the obvious that can get overlooked, and hopefully I'm
wrong.

Tony2

Yes I am using Tracy 2/4 injectors system.
Up until MAP 15" Hg Tracy fires only two injectors. After MAP 15" Hg Tracy
backs off the pulse width of the first two injectors and brings
the next two injectors on line with a pulse width calculated for all four injectors
to provide the same amount of fuel. After MAP 15" Hg both sets of two injectors
are the same pulse width and are increased as the manifold air pressure continues
to rise. I am in the process of changing the rate, on the test bench, these pulse
widths are increased to richen the mixture on the top end.

Paul Lamar

Using Tracy's system, I want to say that you can have different sized
secondary injectors (as compared to the primary injectors), and that
there is a programming mode that is able to be stepped up/down to
accommodate that.. so you can have 550's on the primaries and 1000's or
1600's on the secondaries.

Are all your injectors the same flow?

Dave

I think you are referring to mode 6.
Yes all injectors are currently the same but we have lower flow
injectors we can try on the bottom end.

We need more tables of flow verses injector pulse width for the
several types of injectors out there. Marc Pedings is working
on the where with all to achieve that. Then we need a low cost way
of knowing what those numbers are on the ground and in the air
without the use of an expensive oscilloscope. Tracy's EM2 may be that
device but so far I have no experience with it.

Tracy's idea of being able to change the MAP table in the air is a
good idea but not necessarily the easiest way to to tailor
the MAP table on the ground. What I would envision is a curve
on a computer screen where you can grab parts of the curve
and adjust it. Rhino 3D drawing program has a similar system
called "control points". You grab a point on the curve with a
mouse pointer and drag it up and down to change the whole curve
in a smooth manner. You would then download the new MAP table
through a USB serial interface to the computer.

Another use and advantage of the USB serial interfaces is the ability
to download real time data acquired in the air of water and
oil temps as a function of HP and altitude among other things.

As alternative to this if you change one point in the table Tracy
could automatically adjust all other points to smooth the curve north and south
of the point you choose much as Rhino does.

Also by the way Tracy uses a system where there is a default curve of
pulse widths and MAP table readings are plus and minus this default table.
Currently, other than using an expensive oscilloscope there is no way of knowing
what these pulse widths are. I would prefer absolute pulse width values for
the MAP table numbers so they can be adjusted for different injectors.

Paul Lamar

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