Al Gietzen wrote:

 > > First is that the engine runs better on trailing plugs only than it
does

on leading only

After much double checking, head scratching, and some further testing we
finally concluded that the only explanation could be that the timing was
actually very much early.  And the only way that could be true was if
the timing marks and the pointer did not relate to the position of the
rotors.

By viewing the position of the apex seal through the two sparkplug
holes, measuring angles, etc. we made a new TDC mark on the pulley, and
a new 20 Degree BTDC mark.  Then re-set the static timing on the crank
angle sensor, and fired up.  Ran well, and disabling leading had a
bigger effect than disabling trialing, one would expect.  To verify
timing we put a pressure transducer into the trailing plug hole, ran an
oscilloscope trace triggered by an inductor on the leading plug wire.
One step back on the EC2 timing adjustment gave us the trace we wanted.
(Fortunately, operators know what the right trace looks like based on
their prior rotary development work).  We then ran up to Tracy's
recommended set point of 5000 rpm > 22" MAP (actually 24") and found we
were RIGHT on our new 20 degree mark.  Problem solved.

The earlier timing mark was about 14 degrees too early.  I'm amazed how
forgiving the rotary is for improper timing. It had seemed to run
normally.

I can thank David Atkins for selling me an engine where the timing marks
on the pulley, and the pointer on the front cover didn't relate.  He
obviously was unaware of the problem because when I had discussed the
problem with him earlier, he never mentioned that as a possibility, and
basically said the problem was with Tracy's controller.

Anybody using the EC2 find that the staging may occur at more like

17"

rather than 15.

This one was much easier.  We found that the staging set point in the
EC2 was actually 16.5 -17" MAP.   Easily reset from the control panel.

Al Gietzen

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