There are a couple of good pictures and ideas on this website: http://www.geistware.com/rcmodeling/...es/baffles.htm

In the upper photo showing the seperator plate, notice that air can still travel THROUGH the lower engine fins, but not AROUND them. This is an important distinction. It doesn't matter at all how much air flows through the cowl if it isn't directed THROUGH the fins (or rather excluded from everywhere BUT the cooling fins...).

I also like the flat plate with the "fence" behind the cylinders, and plan to install something similar on my own twin (BME 110). As you notice the air inside the cowl will be excluded from all areas above the baffle, and subsequently guided downward aft of the cylinders to the cowl exit.

There are a couple of good pictures on this site too: http://www.aeroconversions.com/produ...ing/index.html . Notice how (on the VW engine) the horizontal seperator plates and fence aft of the cylinders force as much air as possible to flow DOWNWARD through the fins.

Setting up baffles to enhance downward flow will pick up the forward, aft, and upper side of the cylinder, and with good extraction we will also pull hot air from the exhaust side away from the engine.

Does this help at all or is it just more confusing?