Rob:

You're on the right track but you quit a little too soon!  <VBG>

> I'm no expert, and after consulting a few the two
> non-std things I did are:

You're more of an expert than you realize!
>
> 1) cut a slot in front of #5
> http://rob.com/lancair/2003.08/DSCN6346.jpg
>
A good start.  Now you need a baffle UNDER the horizontal plate which makes
the air stay attached to the lower front fins.  That would be the complete
fix.  It will REALLY cool off that cylinder.  Call me if you want to discuss
this.

> 2) cut a slot in behind #2
> http://rob.com/lancair/2003.08/DSCN6345.jpg
>
Your cutout extends too far inboard.  A lot of air is leaking there and
escaping to areas which are not helpful.  Also, this would work better if
the hole had a box over it which kept the air moving close to the cylinder.
You also need a baffle under the lower rear fins to direct this air to the
*hot spot.*  That will drop your CHT another 10-15dF--at least.  Again, call
me if you want to discuss the details.

Walter