Very interesting table, what sort of performance have you plugged in for the descent? I descend LOP which allows me to “get back” about a third of the cost of the climb, fuel wise, and makes the table much more balanced.
@Peter can you explain why best power is rich of speak? I understood that best power should be peak, stoichrometric, 15:1 given that all parts of the engine, fuel supply,and timing are all optimal. Of course they never are and are therefore different not only between types of engine but manufacturers and add ons also. I should add that therefore all engines are individual and different therefore.
Depends on how you define “best power” 
Yes; stochiometric gives you the most power for the available fuel flow. But these air cooled engines, designed for minimal weight, are unable to run at this configuration, due to insufficient cooling. So if you want to get the rated 250HP out of an IO540-C4, for example, it has to be about 200F ROP where the combustion profile is a lot cooler. The resulting fuel flow is then a ridiculously high 25 GPH… And the fuel servo is adjusted to deliver 25 GPH when the airflow is WOT (wide open throttle) with the mixture lever all the way forward, at sea level, to make all this work.
I am sure you could get 250HP out of a watercooled version, peak EGT, but nobody does it. Not even the most modern car engines, AFAIK, which run well ROP when you floor the pedal. Presumably because the cooling system required for max power at peak EGT would cost too much.
Also a surprising % of the heat in our aero engines goes into the oil; I have some references here.
Another limitation may be that insufficient air is available coming up the manifold, so if you tried to get 250HP while peak EGT or LOP, I don’t think you could. Has anybody tried this? You would have to be quick 
I know you can get 80% at peak EGT, but 100%?
This is the chart that explains the relationship between all parameters.
The main limiting factor is ICP Internal Combustion Pressure.
CHT is a direct proxy for ICP.
Since CHT is slower reacting due to mass, EGT is a good marker for navigating the curve.
Near stoichiometric mixture, there is a perfect balance of fuel and air but the burning of the flamefront is also quickest, leading to higher ICP.
By setting the mixture richer or leaner, the flamefront burns slower, pushing the peak pressure more into the downgoing cycle of the piston, reducing ICP considerably, thus reducing CHT and increasing detonation margins.
BSFC is the Brake Specific Fuel Consumption or fuel needed to produce one HP.
gallois wrote:
can you explain why best power is rich of speak?
I believe the correct answer is the fixed timing is set up that way. i.e. at stoichiometric complete combustion happens too fast to get maximum power. for that engine speed/manifold setting. You are still on the compression stroke when combustion begins some of that heat is transferred to the engine instead of HP. But you can also see from the graph dirkdj posted on rich side the power output is fairly flat. Some engine also can’t safely produce full power at stoichiometric or near, so must be quite rich at take off power the engines in the PA-31 are like this.
Airborne_Again wrote:
Can you do that with SD except by manually trying different levels? AR gives you a table of flight times and fuel consumptions at different levels.
Yes you can:
I believe the correct answer is the fixed timing is set up that way
I am sure that’s true, but the overriding factor must be heat disposal. Already we are looking at climb CHTs approaching 400F in many installations, in warm locations, and you might be looking at 500-600F if you were doing max power at peak EGT.
