Timing adjustment

[Mrcaseymyers]

When I do my mag check before take off i have almost no difference in rpm when running on just the primary. When switching to just the secondary I only get a drop of about 20 rpm. In flight when running on just the primary the rpms drop about 130 but when running on just the secondary it barely loses any rpms. Does that mean I should retard the timing slightly?

[Mrcaseymyers]

I appreciate all the insight from everyone that has so much experience with this. For those who are wondering you need to advance the ignition by turning it counter clockwise. This reduced my egt’s by a significant amount and also allow me to climb at higher rpms. My timing mark is currently about a 1/4” or so to the right of the initial setting where the manual calls for it to be. Not sure why the factory wouldn’t make it easy and just put a mark where it actually needs to be. If everyone has their primaries timed per the manual wouldn’t everyone’s secondary need to be timed in exactly the same location? Hope this saves some people some time and aggravation. I also want to add that I had a significant amount of frustration with trying to adjust the aeroinjector. I was having a hard time with the idle setting for taxing. I was on a 2 mile long runway and by the time I got to the end of the runway ready to take off it felt like my plugs were fouling even though I had aggressive leaned my mixture. After many hours of experimenting I realized that it really had nothing to do with the carb itself. It was actually the way the factory designed the fuel system. My fuel system was set up exactly per the plans and what was happening is by the time I reached the end of the runway I believe my fuel was boiling. I had tried both 93 octane and 100ll and it didn’t seem to make much difference at all. I removed the gascolator and used a inline filter instead. I took out the low spot and made the carb be the low point. I double insulated the line with fire sleave ( one 3/4” and one 1 1/4” over the top of that and that was the perfect size to slide over the inline filter). I was to the point that I was just about ready to sell the plane for 10k just to get rid of the frustration. Now that I have those issues corrected I love it. I’ve flown it 10 hours in the past couple weeks with no issues at all.

[mike.smith]

Welcome to experimental aviation! :-) Every plane/engine is a little different.