flyrotary@lancaironline.net Mailing List Archive

Interesting results Steve. I didn't think a simple across the board increase would be that effective. In view of your earlier results I made a minor change to the EC2/3 software to bump up the injector pulse width but only when the staging point is reached. This only applies to the setup for same sized primary & secondary injectors. With the much larger secondaries on the 4 port Renesis the mixture goes rich instead of lean at the staging point (unless Mode 6 is adjusted to compensate).

I have not flight tested the change yet.

Tracy

On Wed, Mar 9, 2011 at 1:11 PM, Ed Anderson <eanderson@carolina.rr.com> wrote:

Ah, Ok Steve, thanks for the explanation. That's when your adjustment was made (with pulse lengthening HW) in order to show the results on the right hand side of the plot - got it.

Ok, makes sense that if adjusting the map takes care of the staging "bog" then it’s the equivalent of adding 1.2 msec (fuel equivalent) to the values in the Fuel MAP.

Ed.

From: Steven W. Boese

Sent: Wednesday, March 09, 2011 12:59 PM

To: Rotary motors in aircraft

Subject: [FlyRotary] Re: more staging and tuning

Ed,

Those perturbations you see are the result of engaging the pulse width addition hardware and the readjustment of modes 3 and 2 along with a momentary manual mixture change that was unnecessary. I should have labeled three regions on the plot with the area you are referring to as a readjustment period.

That plot was a quick attempt at showing the effect of the pulse width addition in a single session. The adjustments were probably not the best since it was cold, windy, and our latest snowstorm was just getting started. Since this data was collected in my back yard, I try to keep the sessions short for the neighbor’s benefit. So far, though, the horses just across the alley are the only neighbors that have shown any interest.

I suspect that adding the injector lag time is a large part of what adjusting the MAP table is doing when using either of the two tuning methods described previously. The second method may be easier just because the step in the table at staging has already been eliminated.

Steve

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anderson
Sent: Wednesday, March 09, 2011 10:12 AM

To: Rotary motors in aircraft
Subject: [FlyRotary] Re: more staging and tuning

Fascinating, Steve

I presume the perturbation we see in the right side of left plot (Tuning Plot1.jpg) as you decrease engine rpm (and I see a tweak of the manual mixture control -- perhaps to keep the engine from dying?) - the O2 sensor bobbing between rich and lean. I do not see that pertubation on the right plot - is this (bobbing between rich and lean) due to the controller causing the injectors to actually cut off (not open) due to the 1.2 msec delay not being compensated for???

If one had the controller map math, it might be possible to add the "1.2msec" of fuel missing by increasing the MAP value in each bin??? However, I guess (even if possible) it would be easier to compensate by using your method 1 or 2.

Good work, really appreciate you sharing it with us

Ed