I had to go back to my webpage to see what you were talking about. If you look at the right hand picture (upper cowl off, lower cowl on, looking directly from the rear), you will see the bottom edge of the rear baffle---it is a straight edge that passes above all the pipes. Other than the curvy pieces that wrap around the cylinders, there is nothing else below that line. It is all open space. This is why downdraft is so easy to baffle.
I need to update my webpage with all my Cozy stuff. The Longez was sold well over a year ago to a Navy Doc in Biloxi. Not that long afterward, Katrina hit. The airplane was in a large hangar at Stennis Airport. The hangar flooded with salt water, the airplane floated, and when the water receded, it came to rest on its tail. Insurance company totalled it.
It had a very powerful O320 on it with very little hours. Unlike my Cozy, it did not have electronic ignition and fuel injection.