Lets get one thing straight. Fuel injection does nothing for the BSFC

or the

HP an engine will generate.

I agree! The new Triumph Tiger with FI doesn't go any faster than my carbed model (1998).
Though the FI does do better in the rapid throttle response mixture control.

If you run your Lycoming lean of peak the warrantee is void and you risk
burning the very expensive $250+ each sodium cooled exhaust valves

Actually, when you run 50 degrees lean of peak, your exhaust valves run

cooler that when you run 50 degrees rich of peak.  This is because, while
EGTs are the same, the CHTs for the lean of peak condition are quite a bit
lower (45°F lower according to the TCM IO-550 curves!).  It is the delta
between exhaust valve temperature and CHT that conducts heat out of the
exhaust valves and cooler CHTs are better.

Another difference between lean of peak operation and rich of peak

operation is that lean of peak provides a slightly oxygen rich exhaust,
while rich of peak provides a fuel rich exhaust.  There is a theory that an
oxygen rich exhaust stream can affect exhaust valve life due to corrosion,
but I haven't seen any definitive studies on it.  Anyone have access to data
on this?

All this is totally  irrelevant to a rotary engine as there are no exhaust

valves and

you can lean the mixture until the engine quits without hurting the engine.

Its like the price of auto gas being half what it is for 100LL. The exact BSFC
becomes irrelevant. The wankel rotary becomes the  aircraft engine
of choice.
Paul Lamar

Well we are getting into more than what initially meets the eye here. Namely, the speed of
the chemical reaction of the combustion process changes with mixture. Once past your you
leave the 12~15 / 1 ratio of air to fuel the rate of the reaction drops off quickly.

So.... You are leaning the mixture and have lover EGT's, but the actual reaction time is
taking longer to occur and the still burning mixture now flows over the open exhaust
valve, heating it farther, instead of burning, expanding in the combustion chamber, and
exiting.

Klaus' system punches the timing FAR, far forward of the stock settings. while looking at
MP settings. His systems go from 15 to 45 btdc. Now if it would become fully integrated
with mixture control it would seem that the system would be perfect.

Blake

 
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