It helps quite a bit, actually. Both the pictures and explanation.

This addresses my question. as I said above...I've seen/heard many suggestions that air be directed toward the CENTER of the "footprint" of the cylinder...which, quite specifically, EXCLUDES the fins above and below that area. Your statement above leads me to believe I'm NOT completely loopy then...that excluding the fins is as fruitless as NOT excluding the "non fin" parts of the cowl.

Indeed...and again, I notice that while the areas that AREN'T fins ARE excluded...but the ENTIRE fin area is INCLUDED.

Makes sense.

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Again...I think perhaps I asked my original question poorly. What I was really after was whether or not this idea that "air should be directed at/over/through the middle of the cylinder" was really appropriate...that such an idea excludes a large percentage of the "cooling surface" presented by the fins.

I think the pictures and explanation you provided answer that for me. I feel that i was, indeed, on the right track : That "ideal" airflow would be the full body of air flowing over ALL fins, but ONLY over the fins, rather than being wasted flowing through areas that do not contain cooling surfaces.

When air is directed at the center of the cylinder, it will still flow through the fins on the underside, provided there is sufficient pressure differential. The separator plate really just serves to eliminate a circular path of heated air within the cowl (i.e. starting at the mufflers, flowing forward to the front of the engine, aft across the top, down the backside to the mufflers, and recycling forward again...).

This one step, although counterintuitive, is certainly better than nothing.

Here is some good information on baffling, air flow and extraction.

http://www.prme.nl/forum/viewtopic.php?p=506#506

Hello gents (you too Pat and Ralph),

Does anyone have pictures of a good round cowl baffel setup? I'm putting together a 95" Pitts 12 and want to keep my DLE 111 in good shape. I looked at the links you have all provided and didn't see anything with round cowl detail.

Driesbabe just posted some pictures in another thread of a method that will work quite well. Suppose I need to find that thread and link it here...
[link]http://www.rcuniverse.com/forum/m_9273918/tm.htm[/link]

As for the best baffling method...

The best would have an inlet duct that leads directly to the cylinders. The cylinders would have a shell constructed around them (encompassing) so close fitting it likely touches the edge of the fins. All the incoming air would be routed into the shell, reduced in velocity after entry to provide time for the through flow of air to absob BTU's, and directed out via another duct. There would be a passive secondary means to assist the extraction of the hot air. Lotta work!

Thank you sir! Have a great Thanksgiving.

Here's some more to look at and read on the topic: There are examples all over the forums, and various websites on this topic.

http://www.cactusaviation.com/Tech/baffling.html

It is said that there are a company acclaimed their DLA112 will replace DLE111,has anyone heard that?and their engines is lighter 50g than DLE111.I want to test this engine?has any one have tried.