Another thing to try is to set the MAP table write width to

minimum (in mode

2) before doing the mode 1 programming.

Some EC2 users avoid the transition stumble by moving the

transition point

to a different manifold pressure (in Mode 7).

Unfortunately, Chuck has an

early EC1 controller which has a fixed manifold pressure

for stagging.

Tracy Crook
tcrook@rotaryaviation.com
www.rotaryaviation.com

   I tried carefully programming on the ground with the write width set

at

minimum and very slowly increasing the throttle. Still no joy. As soon

as I

got to 16" MP it started surging at 1 second interval. Then I went

flying

and programmed at a safe altitude with minimum write width. I finally

got a

good result by hitting the program button at just the right time, at

minimum

RPM of the "surge" and setting it richer in that area. Now it is much
better! Three things were working against me, 1. the O2 sensor responds
slower at low power, 2. there is no way to "see" what is actually going

on

in the MAP table programming, and 3. MP starts increasing again below a
certain RPM.

I think #3 comes from having the secondary ports open all the time and

the

late closing of the secondary intake port. Of course when MP rises, so

does

the amount of fuel, making it too rich when it doesn't need it. I was
considering installing an accumulator in the vacuum line to the ECU to

slow

the response, and thus surge cycle time, to where it might be easier to
program. A software or hardware integrator (?) should accomplish the

same

thing. We don't need fast throttle response in an airplane.     The EC1

is so

easy to program at 17" MP or above that I just did not expect it to be

so

critical in the staging area. I had it programmed real close before, but

I

was trying different ignition timing, and probably needed new spark

plugs,

and got the programming all screwed up by trying to use the easy
programmability (is that a word?) feature of the EC1 to compensate. I

will

try to leave the EC1 alone after this. Anyway, Thanks, guys for the

help. I

get stuck in a rut thinking about a problem a certain way and it sure

helps

to see things from a different perspective.

And thanks, Tracy for the generous offer to upgrade my EC1. I may do

that

later when I run out of things to do :-) but as long as I can make the

EC1

work, I will keep it so I will not have to rewire everything for the new
connector on the EC2.

Chuck Dunlap

Yes, the point where the injectors stage is by far the hardest to program.
Everywhere else it is so simple that it leaves you unprepared to deal with
that one spot.  I'll have to give this subject some more thought and see
what I can do to make it easier.  Being able to move the stagging point (on
the EC2) allows you to move it to a place where it isn't so sensitive but
doesn't completely eliminate this.

Tracy Crook
tcrook@rotaryaviation.com
www.rotaryaviation.com

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