George, Skip,

 

I've been trying to keep up with this discussion.  I recall a conversation with Tim Ong a year ago when I received my ram air induction system, the first shipped from Lancair for the ES.  He mentioned that trying to run LOP might cause excessive roughness due to the difference in pressures caused by the ram air.  He said someone (I'm assuming it was a Legacy) had to add some additional plumbing to a pressure sensor that is part of the fuel injection.  Is there some sensor on the IO-550N that senses pressure under the cowl?  Do you know what Tim was referring to?

 

Mike Easley

Colorado Springs