I have always installed the NVA on my engines with the fuel inlet on the exhaust side of the engine on both side mounted and inverted engines.  My purpose was to facilitate NV adjustment without burning my fingers on the muffler.  Seemed logical.

This past Thursday while flying at Brodak's, a very good pilot/builder and friend suggested that I reverse the NVA so the fuel inlet was opposite the exhaust side.  The plane I was flying is a SV-11 with a Super Tigre .60 for power.  I never could get the engine to break (4/2) consistently.  It would go lean after a half lap.  We reversed the direction of the NVA (installed it with the fuel inlet opposite of the exhaust) and the engine run was perfect on the next flights.  Great 4/2 break on every maneuver.

My friend's reasoning is that because, while in flight, centrifugal force pushes the fuel towards the outside of the flight path and with the NVA's inlet on that side, better fuel supply/flow is achieved.  Whatever the dynamics are, at least in this instance, it made a big difference. On profiles with side mounted engines it probably makes no difference but on planes with inverted and upright engine mounting, apparently it does.

Perhaps this has been discussed before but it is new to me.  Just wondered if anyone else has any thoughts on the subject.

Regards,

Joe