Paul,

    The oxygen sensor will give you an indication of your air/fuel mixture
ratio.  A mixture rich in fuel consumes more of the oxygen in the intake
charge and conversely a mixture lean in fuel consumes less oxygen.  The
voltage output of the O2 sensor reflects that status.  So it can be very
valuable in evaluating your what your engine is doing.  In addition, while
EGT can provide useful information regarding mixture, it is very slow in
response time compared to an O2 sensor.  I find the O2 sensor indications so
useful that I do not feel comfortable contemplating flying without one
anymore.

  The combination of the O2 and EGT sensors and a fuel flow sensor really
provide just about all the useful information about your engine functioning
status that you would need/could use in flight.  If your O2 sensor in
indicting rich and your fuel flow is high and your EGT high then you should
be producing power.  If your engine should start to stumble, its really
useful to know if its because of too much or too little fuel.  I have two
EGT sensor (one in each header) but only one 02 sensor.  Unless your fuel
mixture is greatly out of balance between your two rotors (which your EGT
may indicate) then one O2 sensor should be plenty.  Actually if they are out
of balance, then you need to fix that rather than having two O2 sensor in
any case.

I really don't know whether it would make sense to install two EGT sensors
in your cast manifold.  I suppose you could drill holes right at the exit to
each port and install one, but how much it might be influence by the exhaust
from the nearby other port is hard to say.

My 0.02 worth

Ed


Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
----- Original Message -----
From: "Marvin Kaye" <marv@lancaironline.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Friday, March 19, 2004 9:38 AM
Subject: [FlyRotary] Re: Where to install EGT sensor?


> Posted for "sqpilot@earthlink" <sqpilot@earthlink.net>:
>
> RE: [FlyRotary] Re: Where to install EGT sensor?Err....I should probably
have
> mentioned this, but I didn't because I don't understand the silly thing.
I DO
> have an oxygen sensor in my manifold, and the ECU instructions said to
hook
> the black wire to it.  What will the oxygen sensor do for me (or not do),
and
> is this something that can take the place of an EGT sensor?   Inquiring
minds
> want to know. Thanks for walking me through this....I am embarrased to
admit I
> don't know very much about these items.  Thanks for your all those who
replied
> already.  Paul Conner
>
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