I know of at least two Cirrus SR22's that have the same high oil temp problem in very hot climates.  Yes, you could change the N cooler to the G.  The only problem is that the warantee is void at that point, and you would have to change the engine data plate.  Like I said, TCM has no plans to change  because they feel anything under 240 is acceptable.   Yes, there seem to be some exceptions in this issue, and it seems that some of the IO550N's work ok (although I haven't seen it personally).  As I recall, someone "de-burred" or did some modifying on the vernatherm and it worked much better, but I have no direct knowledge what it was.  I've also noticed that the Legacy seems to have less problems, so the only explanation must be the cowling (and speed).   Keep in mind that even though there are small leaks in the baffling, there may be many of them that add up to a huge amount of air pressure loss in the upper plenum area that adds to the problem.  Also, the Legacy has a much better exhaust area design in the lower cowl.  Most ES guys are installing mini Dolly Parton's to help.  This is one major thing that should be done at the factory, and should have been done long ago.  Modifying the lower cowl mold to match that of a Legacy would be a major improvement.  I know of two ES's with LNC4 upper and lower cowls, and they have no cooling issues.  Yes, they are slower though. 

Ron Galbraith

So would it be correct to say that since we are flying
experimental airplanes and if the oil cooler from the
"G" is interchangeable with the "N", that this would
be a solution?

My brothers Cirrus has the "N" and has no oil temp.
problems and I know some Legacy owners with tighter
cowls, smaller air inlets than the ES that have no
cooling problems. How would you explain this?