Procedure for best rate of climb

[Antoine]

Paul, Ok makes sense to me.

To answer your question, I do the initial leaning exactly like Robert explained in the post above.
My cruise climb settings are 2500 RPM, 90 KTAS (not KIAS, the difference becomes significant with altitude) and best power.
I found that 90 KTAS will deliver enough airflow at any altitude that I don't have to worry about CHTs passing 400.
But unlike quite a few others , I believe that 400 F is actually a healthy CHT in the climb and here is why.

The heat exchange is a function of the temperature delta between the hot surface and the cooling medium (in this case: air). The larger the delta, the better the cooling. Our planes need every horsepower available in the climbs. Setting mixture to richer than best power will produce less power, while wasting fuel for cooling purposes.
I'd rather use all of the potentially available power to shorten the climb time. On a hot day, this will give CHTs near 400 F. On a cold day, it is more like 370-380.

One very important parameter though is RPM. As Brock mentioned in the supercharger thread, RPM plays a key role in heat generation (+10% RPM = +21% heat). This gives us one additional option for tweaking.

[Tommy]

Paul, Ok makes sense to me.

To answer your question, I do the initial leaning exactly like Robert explained in the post above.
My cruise climb settings are 2500 RPM, 90 KTAS (not KIAS, the difference becomes significant with altitude) and best power.
I found that 90 KTAS will deliver enough airflow at any altitude that I don't have to worry about CHTs passing 400.
But unlike quite a few others , I believe that 400 F is actually a healthy CHT in the climb and here is why.

The heat exchange is a function of the temperature delta between the hot surface and the cooling medium (in this case: air). The larger the delta, the better the cooling. Our planes need every horsepower available in the climbs. Setting mixture to richer than best power will produce less power, while wasting fuel for cooling purposes.
I'd rather use all of the potentially available power to shorten the climb time. On a hot day, this will give CHTs near 400 F. On a cold day, it is more like 370-380.

One very important parameter though is RPM. As Brock mentioned in the supercharger thread, RPM plays a key role in heat generation (+10% RPM = +21% heat). This gives us one additional option for tweaking.

Right on. Same procedure used here.
Works like a charm.

[PapaSierra]

Thanks everyone for helping me gain a much better understanding of TO power settings!! I have had the distinct pleasure of getting to know most of the folks at Premier Aircraft at KFXE. Their chief pilot, Corbin Hallaran, has offered to spend some time with me as well and he knows the DA40 well.

I have an external power system for the ground and will spend some time gaining expertise on the glass. I will also spend a lot more time on my next run up, really taking the time to see and understand the relationships you all have described.

I feel like I'm getting to know all of you yet each of us will likely never meet most of members of this board! Sad... Maybe we could plan some events that would even get the folks far away from each other to come visit!

[rwtucker]

You are welcome Papa Sierra. One of the great things about our group is that we are all students of one thing or another, and all teachers of something else (mostly a student in my case ). Hands down, it is the best education I have had in GA flying.