Sounds like it's working for you but if those check valves are "good" ie, don't leak,  the MP won't go up fast enough at the EC2/3 port and the engine will probably bog down and die when you open the throttle (especially if done rapidly)..   Check your throttle response to be sure the EC2/3 sees the true MP when you go to WFO.

Tracy

 

On Fri, Jan 20, 2012 at 6:04 PM, Mark Steitle <msteitle@gmail.com> wrote:

I made a major breakthrough today.  In preparation for hooking up my new Hytek data logger, I decided that it would be a good idea to install check valves in the vacuum lines leading from each rotor housing.  (For those who are unaware, I am running a peripheral port 3-rotor with a slide throttle TB.)  My system measures MAP from the unused oil injection ports in each rotor housing.  Not sure what possessed me to do a ground run right then, but I decided to do a ground run after installing the check valves.  Now keep in mind that typical MAP readings at idle up to this point was approx. 17".  This has been bugging me, but it didn't stop me from flying.  Well, today's MAP readings were in the 14.4" - 15.0" range.  Then it dawned on me that the way the vacuum lines were plumbed the EC-2 would see an average of all three rotors.  Since each rotor is 120* (crank degrees) apart in their 4-stroke cycle, the MAP would be quite a bit different for each rotor.  By installing check valves in the vacuum lines, I have now isolated each rotor from the other two and am measuring the lowest vacuum.  Idle is now down to a respectable 1500 rpm, but the mixture has gone way lean, so it appears that a re-tune is in order.  I'll probably re-set the EC-2 to the factory defaults and start the process over from the very beginning.  

I would like to strongly suggest to anyone that is measuring MAP in the rotor housings to install check valves in each of the lines.  Your EC-2/3 will thank you for it.  

Mark