Variable Advance - Any improvement?

I?m interested to know if anyone has experimented with EI timing changes in flight? I have a set of Pmags and considering if there are significant advantages to firing the ignition earlier than the 39 degree maximum advance and/or other general tuning?

The manual seems a bit vague on what actually takes place under the hood of these things. I assume that the advance is related to RPM and MP, but what the exact relationship is not immediately obvious.

Richard

RV-7A Phase I

When the P-mags are turned on, the software initialises to use the A or B curve depending on the jumper. Opening/closing in flight will not change which curve you use.

EICAD

Hi Steve,

With EICAD you can advance the timing while the engine is running and you are not limited to the A or B curve. See http://www.emagair.com/EICADII.htm or the latest installation manual for 114 series.

Cheers
Richard

The LightSpeed Plasma III units allow monitoring and manually adjusting timing while in flight. Several of the racers flying Legacys use this option.

EIcad

I used a laptop with eicad to vary the timing curve in flight and settled on a max advance of 42 deg. It allows me to run very lean at lower power settings.





I cruise at about 55% power, LOP, with good results(150KtsTAS on 6GPH) This with an O-320/carb/Hartzell.

I heard some guys we know are working on a way to do this without a laptop. Maybe they will pipe in.....