xerj wrote:

Yet another question.

Say you're at altitude and it's time to lean the constant speed engine(s).

You pull back on the mixture control, the EGT starts to go up. The engine
"sounds" more powerful as you do this. The prop might speed up momentarily
until the governor does its stuff and keeps it at the selected speed. You
reach peak EGT, and if for argument's sake you're going for a certain
degrees ROP, you ease the mixture forward until you hit the target temp.

While you're doing this, you're also watching the fuel flow meter that you
have installed. As you pull the mixture back, the fuel flow starts to go up
as the power increases, and peaks with peak EGT.

That's wrong. The fuel flow goes down as you pull the mixture out. The
fuel flow always goes down when you pull the mixture out.


The thing that has me a bit confused is this:-

I understand that roughly speaking increased power = increased fuel flow.
Therefore, it makes theoretical sense to me that as you pull the mixture
back and get closer to stoichiometric that you will see an increase in fuel
flow because the power output of the engine is increasing. What I can't do
is explain why mechanically.

You are wrong. The flow goes down because you were over rich for
takeoff and climb.