Subject: How to tune with ADI?
From: Rotary Engine
Date: 8/29/2011, 7:49 AM
To: AAA Put this in the To box



Ok,  So I have the new ADI system installed and working....  I think?

Some of you smart racing guys probably have experience with ADI.

Most of the instructions that come with tuning it are directed toward car
guys that have computers and knock sensors.  All they do is turn the system
on and the computer allows more advance because I is not sensing any knock.
The only real advise I have so for for me is that I should be running just
less than the amount of ADI that it takes to bog down the engine.  My
system
is a fixed flow so I don't have much choice but it seems to be about right.
If I use straight water (which I did for initial testing), the engine bogs
after about 10-15 seconds of ruining the ADI system.  But when I uses a
50/50 mix of water and denatured alcohol (too hard to find methanol around
here, but close enough) the engine does not bog.

So assuming my amount of ADI injected is about right, now I am supposed to
be able to lean to better power and advance the timing a little.  But how
much?  For the last testing flight I was using EGT for lack of a better
guide.  When the ADI comes on, my EGT drops by about 30 deg C, and there is
a hint of roughness to the engine.  I can then lean a little and the
roughness clears up.  For my test flight I leaned until my EFT came back up
to where I normally limit it (890 deg C).  But if I then add 5 more inches
of MAP, there is still a hint of roughness even at 890 deg and I get the
sense that it wants to be leaned a little more. But I am afraid to do
that...  We are talking 45" MAP and 7300 RPM here (185 KTS indicated
(Vne) and climbing at 500 fpm).

So here are my questions:
Is EGT a useful tool here, and does leaning to get the EGT back to 890 make
any sense?
Since Methanol will do such a good job at preventing detonation, is it safe
to lean further toward best power (peak EGT)? (note, that will be hard on
the turbo...  I need to remember to bring the spare one to Reno)
How much advance do you think i can add?  I was previously ruining 5 deg
ahead of Tracy's recommended initial set up.  Can't give a number because
the EC2 retards the timing with higher MAP's.  How much, I have not heard.
I can easily add one deg at a time using Ed's EFI monitor.  But without a
knock sensor am really in the blind.

Thoughts?

--
David Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRoster.net


I have a knock sensor I can loan you if I could only find it. On the turbo
engine it screws into the center housing. It generates an audio sound you
can feed into
the music input of your intercom. I am sure that Mazdatrix has one.
You can get an amp from MSD. You need it now.

Paul Lamar

Thanks Paul, I think I will take you up on that, although I may just buy
one.  I have a stock turbo II sensor around somewhere.  I assume that works
just as well as the Bosh and others?

-- 
David Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRoster.net


I'll check in the hangar today and see if I can find it.
I can't recall seeing it lately. Could be in any of
50 card board file boxes :)

It is amazing how simple they are when the brain can listen to the knock sensor.
The brain makes a great sound discriminator. You use a broad
band audio amplifier and feed it into your head set.
Test it by smacking the center housing with a hammer.

The Mazda unit is tuned for the rotary. The RX8 has two. One for
each rotor housings but you must have RX8 rotor housings

BTW sometimes it is too late if it detonates as that can crack
an apex seal. Francois told us it is near impossible to crack
a Iannette silicon nitride apex seals no matter how hard Mistral
tried. Stock cast iron cracks easily. The 3rd gen got a real bad
rep for that reason.

Rumor has it Tracy's steel seals are harder to crack but they wear
out the rotor housings quickly and they are 10% down on compression
when first installed which may be a good thing for a turbo :)

Paul Lamar
-- 
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