When I first started flying my ES with the ram air system, I would apply full power on the runway and then reach down and open the ram air.  I got a pretty good kick in the seat.  I was only going 5 mph but had a significant increase in power.  I assumed (maybe correctly) that the "kick" was due to the filter restriction, not the ram air.

 

I have since sliced off the ram air side including the butterfly valve and replaced it with another K&N filter.  No loss of MP and now I fly with 100% filtered air.  The oil runs about 5 degrees cooler without the tube partially blocking the left cowl inlet.  Interestingly, I ran a test before I cut the thing apart and the butterfly valve isn't even close to airtight.  So during taxi you could be breathing in some dirty air.

 

My plan (another in a long list of modifications) is to route the right side of the Y tube below the deck for alt air.  I'll use the butterfly valve to control it, and have the smaller filter on the alt air side.  The design is similar to the Columbia.

 

Mike Easley

Colorado Springs