Art
<<are you doing anything to manage the
air flow under the cylinders>>
I didn't change anything below the cylinders
this iteration. The mod targeted pressure recovery and
sealing above the cylinders. Still on my to-do list is a modification to
the exit. Later Lancair models have nice exit tunnels on either side of
the nose gear which makes work in this area much easier.
<<I
looked at the plenum but with the
reduced volume over the engine I wasn't sure
there would be a gain.>>
The volume difference is not the driver.
The gain comes from better control over pressure recovery and
sealing. 360 inlets have a very high inlet velocity which makes them
more suseptible to problems. Sealing is, of course, a universal
issue.
<<Then there was the work to make
one.>>
This is a real deterrent. Unfortunately changes
like this become major projects. I am certainly glad I did it on my
plane, but since your temps are already good, motivation levels would
certainly be lower. To evaluate the potential gains ahead of time
one would need to measure mass flow and pressure at key points
in the existing cooling system - not a minor task
either.
Chris