Surefly ignition in the -10

[togaflyer]

For those with an IO 540 in their -10 with a Surefly ignition (single install) questions????

Are you using the fixed timing or the advance timing settings….

For those that allow timing advance, what CHT increases have you seen, especially on hot days. I fly out of the Florida Keys a lot.

Are you using massive or fine wire plugs and what plug gap have you found works best.

I have a Bendix impulse mag that will remain on the left side. Does it need to be grounded for the start or let it fire off also.

Any recommendations on the install.

Thanks much…..

[lr172]

No surefly, but do have EI in my 10. I feel that I am saving close to one GPH at cruise by having more than 25* of advance, along with balanced injectors. I flew back from Iowa yesterday and at 7K' was getting 165Ktas at 10.5 GPH. At 14K' I get 165 around 9 GPH.

My system is variable via my choosing, not just a fixed advance table. I do have multiple tables for ROP/LOP as well as a knob to increment/decrement from those tables. I run 23* at 29" and this goes up as the MAP decreases. That said, I need to run lower advances if I am climbing ROP. MAP decreases as you climb and therefore a stock adv table will keep advancing eventhough you are ROP and it is raising CHTs with no performance benefit. In these cases, CHTs can climb 30-40* or more beyond a lower advance. If I am climbing LOP, then the advance is beneficial and have no CHT issues.

I am a true believer in the benefits of advance for LOP cruise, but not so much with those systems that have unchangeable advance schedules. I would recommend the SDS system, as it allows you to build tables that truly work and gives you a manual switch to go between tables you build for LOP and ROP operations. This is a HUGE benefit IMHO.

Lean mixtures like more advance & rich mixtures do not. Gross simplification and you can search here for more details.

When the advance is matched to the conditions, you WILL NOT have CHT issues. If you can't properly match the advance to the conditions, you likely will see elevated CHTs, when ROP, compared to 25* fixed mags in the climb phase-especially above 6-8K'. A surefly with fixed 25* advance will behave exactly the same as your mag.

Larry

[rvanstory]

Originally Posted by togaflyer

For those with an IO 540 in their -10 with a Surefly ignition (single install) questions????

Are you using the fixed timing or the advance timing settings….

For those that allow timing advance, what CHT increases have you seen, especially on hot days. I fly out of the Florida Keys a lot.

Are you using massive or fine wire plugs and what plug gap have you found works best.

I have a Bendix impulse mag that will remain on the left side. Does it need to be grounded for the start or let it fire off also.

Any recommendations on the install.

Thanks much…..

I’m have SureFly set with variable timing. Have not “compared” CHT’s to fixed timing, so no data to offer. But, took off yesterday from Abilene TX when OAT was 108 degree’s. Hottest CHT (#6) got to 419. I know many are scared to ever get above 400, but I’m ok with 419 as it was very temporary on climb-out. My personal max on climb out CHT is 430. Lycomings can handle it just fine. In cruise it was 380. Others around 360. On “normal” summer days in South Texas, hottest climb out CHT is 410 and cruise is 370.

On plugs, I use fine wire. If I recall correctly, gaps on Slick Mag set to .016. SureFly EI set to .025. I think you can go up to .030 on SureFly if you want.

Call SureFly tech support. They will know best.

[togaflyer]

Larry thanks for the input. I’m not at the level to want to be manually adjusting my timing. That is for much smarter people then I. Randy, did you gap your fine wires to 25. Did you have any issues with bending the tab. I read where there have been issues with breaking when bending them.

[rvanstory]

Originally Posted by togaflyer

Larry thanks for the input. I’m not at the level to want to be manually adjusting my timing. That is for much smarter people then I. Randy, did you gap your fine wires to 25. Did you have any issues with bending the tab. I read where there have been issues with breaking when bending them.

I did bend my own, but bought the tool from ACS for that purpose. Tempest will do it for you. But shipping costs are more than the tool. It was simple and straightforward.https://www.aircraftspruce.com/catal...lickkey=205315

[togaflyer]

Thanks. I found this from Tempest. They go to 36 on fine wire for e mags.

Standard Ignition Fine Wire spark plugs are gapped to 0.017” – 0.021” from the factory and High Energy Electronic Ignition Fine Wire spark plugs are gapped to .036” from the factory. The side wire itself should be flush with the top of the center electrode. If the gap exceeds this tolerance, the side wire can be gapped during regular maintenance. The Iridium material has outstanding resistance to electrical erosion, but is very brittle. Using small needle-nose pliers, grasp the side wire perpendicular to the face of the plug. Smoothly twist the pliers one time only to achieve the proper gap. There is very little spring back at the electrode when bending. Any additional adjustments are not recommended due to the brittle nature of the material.