Easy to install...only add a power wire

My IA and I installed a SIM4N in my Piper Archer. It took the two of us about a full day to do the install, largely because part of the planes interior was removed to run about 12 feet of 12 guage wire between the battery and the SIM. We also had to round up a gear puller to transfer the right magnetos drive gear between it and the SIM replacing it, and remove the grounding tab on the starting switch so the engine would start on the SIM as well as the impulse coupled mag on the left. Keeping the impulse coupled mag is not Sureflys first choice for install but it made economic sense in this case because the left mag had been recently rebuilt and it was about time for the right mags overhaul. So far I have two flights with the SIM installed. The starts are quicker and smoother and require less prime, the bottom cold idle moved up from a slightly uneven 550 to a smooth 650, and the 2300 RPM low altitude lean cruise fuel flow dropped from 6.8 to about 6.5 gph. Im expecting to see a greater fuel % savings when I fly at higher RPMs at a greater altitude. As you can probably, tell Im happy with this product!

surefire mag is not complete. you have to buy hose and brass barb, that doesnt come with it. dumb. It would only cost them $5 to include it. Called Tech support about buying AN816 fitting for manifold pickup and hose, was told cant as it wouldnt be FAA approved. WTF?

I have about 30 hours on this installation on an O-360 powered Maule. The installation was a bit tricky because the SIM is larger than a Slick 4300. I ended up having to replace an oil line fitting and do some re-routing but thats an engine specific issue. The aircraft starts amazingly well now, so I am very pleased about that. As a drop in replacement for a mag, its 4-5 stars, only gripe is the lack of a hose barb. If you are looking for variable timing upgrade this is a 3 star product. One of the things that drew me to the Surefly SIM was the advanced timing but now that I have some hours behind, I have switched it back to fixed timing and it will stay that way. I fly out of an airport at 6800ft MSL in Colorado and during most summer mornings the DA is anywhere from 8000-9000ft. This equals about 21 of MP at takeoff, which happens to be about where the SIM goes to its full advance of 38 degrees regardless of RPM per the techs at Surefly. As the weather warmed up I noticed that the plane had a significant lack of power when compared to how it flew in similar conditions with two Slicks. 300-400 FPM climb vrs about 700 on a high DA day. After taking to Surefly and finding that the SIM was running at a full 38 degrees of advance even at 2700RPM at takeoff, I switched it back to fixed timing and my power immediately came back. I spent a substantial amount of time reading up and what I am finding is if you are looking for best power rich of peak (at takeoff, in this case) a significant timing advance will cause a loss of power and high CHTs. My experience seems to support this. I have no doubt that lean of peak the advance feature is great to have at high altitude cruise, but if you are trying to take off from 7000-8000ft runways in anything over standard temp, you will not like the performance. As a drop in replacement for a Slick, I am very happy. As a drop in upgrade for advanced timing for aircraft that live at high elevations, look else where.

Some additional information on using the Surefly SIM. Ive modified my mag check procedure to avoid any stumbling and backfires when the SIM is turned off and on again. Since this only seems to happen above 1000 RPM, I take the engine down to idle before turning the SIM off or on i.e. advance the throttle to normal mag check RPM, check carb heat, turn switch left one position to see the drop on the left ignition (Mag), reduce RPM below 1 K, turn switch one more notch to the left so the right ignition (SIM) is running, advance the throttle to check its operation, reduce throttle below 1K again, then turn the ignition back to both. I compare throttle positions for each ignition position to verify they meet the requirements for safe operation.