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Surefly ignition in the -10

togaflyer

Well Known Member
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…..
 
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
 
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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.
 
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.
 
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/catalog/topages/gapsettingtool3.php?clickkey=205315
 
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.
 
Considering getting rid of a mag and replacing with SureFly or SDS for my RV10 with IO-540-D4A5. How is everyone still likeing their SureFly? Is anyone using the Advance feature or just using it with the fixed timing setting? I can't see any tables or data on the SureFly site that indicate exactly how the advancing works at different power settings just that it will advance up to 38. From other aircraft forums and threads it seems there were not that many people using the advance feature for the SureFly.

SDS seems like a better set up since you can program it but it will require a bit more work installing than the simplicity of the SureFLy setup.
 
Surefly definatly to easiest replacement EI. Same plugs, same wires, same ignition switch. Easy install per manual. I use the advance and don't see any changes in CHT's. Texas heat no problem.

It is just a little longer than a Slick which forced me to remove the breather tube for install then reinstall breather. No problem since you never need to remove it for the life of the engine.

I put the Surefly on the left, removed the retard mag and Slick start. You start on the Surefly as if it were an impulse or retard mag. Normal Slick on right is off for start.
 
Joe, Thanks for the feedback. Using the advance function of the SureFly do you see considerable fuel savings over your previous mag & slick start? I know what the website claims but I am always interested in feedback from individuals using the actual systems. I am in Texas as well so good to know CHT's are the same.

You bring up another question for me. I have a keyed ignition start so it clicks to left, right then both (mags) then start as you turn the key. Is it necessary to only start on SureFly and not both SureFly and Mag on? If so I may have some additional required rewiring.
 
I have an IO-360 and run a Surefly on the right. I decided to see how it went for a bit and then at some future date consider putting a second Surefly on the left. The Surefly SIM4N went on at about 15 hours TSN so I had some basic figures to compare but as the engine was still settling in I don't think it was worth taking too much notice of the data. I set the timing to be fixed since there was no point having variable timing when the left ignition was still an Impulse Mag. Its been operating very well and I'm extremely happy with my decision to install one.

I removed the bridge from the ignition switch so both the Mag and the SIM are available for start. I'm not sure that was really necessary. I didn't notice any improvement in my starts as a result of fitting the Surefly but others report they do.

I've just completed my first 100 hour/Annual (today) and I've never seen plugs as clean as these were. I use standard massive electrode plugs and I left them gapped at the factory setting to begin with (when I had two Magnetos) and have not adjusted them since installing the Surefly. I was going to let them open naturally over time. They're currently sitting at a gap of about 22 thou.

I have just purchased a second Surefly SIM (4P) for the left side. I was going to install it this week but decided I would leave it for a few more days as I'd like to look at a Monkworks Alternator as a standby power source. Going from one Magneto to no Magneto puts me over to the "dark side" where I'm now very reliant on the electrical system. I have a backup 3Ah battery but it was installed to provide a backup to the GRT screens and I might repurpose it for the Surefly instead. Still considering my options on this one. I'm only flying VFR.

Once I do install the second Surefly I'm going to set both of them up for variable timing. All my flying is 9,500 feet or below and I run LOP at all altitudes in the cruise and I lean on climb above 5,000 feet. At 6,000' I regularly see 29 litres per hour at 2400 RPM and while that's not "outstanding" its a lot better than 38 litres per hour others have used as their baseline. My CHT's are all around 168 C (334 F) in flight with a split of never more than 10 C between the hottest and coldest. On the hotest days in summer I saw 210 C (410 F) just after take-off but these have settled down further and 195 C (383 F) is pretty typical now during that first minute or so after take-off.

I'm looking forward to getting the second SIM fitted and comparing the LOG files from before and after the change.

Oh... and installation is very easy. I like that.
 
For those with an IO 540 in their -10 with a Surefly ignition (single install) questions?

Rich, just install it, set fixed timing, fly ten flights or so with the EIS logger running, then switch to variable and repeat. Apply Excel-fu.

It will be fun and educational. And you can't hurt anything.
 
If I am climbing LOP, then the advance is beneficial and have no CHT issues.

Larry, I fly LOP in cruise but haven’t played with LOP in climb. How do you set LOP climb power and at what altitude do you start leaning?

To the OP’s question, I have one mag (non-impulse) and one Lightspeed on my 10. The Lightspeed runs an advance table and I don’t have any major issues with CHTs. LOP I see 340-360 on the CHTs. ROP on a hot day in climb they go higher on initial climb, but come down with 120kt climb. ROP in climb they rarely hit 400 and usually because I’m climbing too aggressively. No CHT issues ROP in cruise.

Starting is routine when cold. Hot starts took me awhile to figure out, but I’ve got it down now. It doesn’t start like a car as some electronic ignition companies claim.

I don’t use fine wire plugs. Plugs on the Lightspeed are always spotless and you can tell they fire hot. The mag’s plugs look like you’d expect for an mag. Every time I compare plugs it reinforces the value of modern electronic ignition systems.
 
Joe, Thanks for the feedback. Using the advance function of the SureFly do you see considerable fuel savings over your previous mag & slick start? I know what the website claims but I am always interested in feedback from individuals using the actual systems. I am in Texas as well so good to know CHT's are the same.

You bring up another question for me. I have a keyed ignition start so it clicks to left, right then both (mags) then start as you turn the key. Is it necessary to only start on SureFly and not both SureFly and Mag on? If so I may have some additional required rewiring.

Fuel consumption with EI is a function of how lean you run your engine. That in turn is a function of your gami spread. Listen to Bush for more details. I have a very good gami spread (<.2gph between cyl) but don't notice much difference in ability to lean any more than previous (you can only lean until roughness sets in....at the cost of airspeed). My compromise of lean enough vs. fast enough and smooth enough is right around peak EGT which is below peak power and peak CHT. If OAT is high and I need to get cruise CHT's down a bit I'll go a little leaner and slow a bit.

Bottom line, I don't see any difference with my new setup. My happiness is not needing to remove every 500 hr for service.

As for your comments on starting, it remains the same as existing. If the other mag is NOT impulse or retard type then it should be OFF for start. They key switches are normally wired to accomplish this by grounding the non starting mag in the start position. If you have individual switches, leave the other mag off (grounded) for start.
 
Bottom line, I don't see any difference with my new setup. My happiness is not needing to remove every 500 hr for service.

With an impulse mag on the 540 SB1-98A says remove inspect every 250hrs!
540's don't like impulse mags.
 
Prop.....

Also consider which prop you have and manufacturer recommendations. I have a WW300C on tap for my -10 project and plan on a single Surefly + Mag. For EI (more specifically PMAG), their documentation states 'jumper wire must be installed' for timing, meaning this will limit the amount of advance. In speaking with the Surefly group - their advance timing goes way beyond that of a PMAG with the jumper wire installed and there's no way to dial it back.

So, based on prop manufacturer guidance, I believe I will need to run the stock/fixed 25 degree timing setting.
 
As another option, the six cylinder pMag. This is running on my old RV-10 for over two years (and ~600 hours) and has proven its worth; ~1gph drop at 8K’ and above cruise for the same speed. My Lancair IV neighbor is equally pleased with this ignition running his Continental IO-550.

The six cylinder pMag bottom and top timing set points are established during install. We set the base at 25 degrees BTDC and the most advanced at 34 degrees BTDC. Of note the cruise conditions to get to 34 degrees are rarely achieved. The pMag comes with a switch that, if moved, returns the timing to whatever is set as base (e.g. 25 degrees in this example), and this can be done inflight. While not used on my old RV-10 I understand that this might be useful for engine break in and some turbo charged engines.

For the standard IO-540 the pMag uses NGK BR8ES plugs, so we tend to replace instead of clean each year. Add to that the “it makes it’s own power, just like a mag” and I suggest this to be a good option for many.

The beta version of this pMag had some issues with drive journal wear. The remedy was to replaced these journal bearing were with ball bearings. Essentially all of these pMags have been upgraded - as are the now production models.

My new RV-10 projects Cold Air Sump IO-540 will be sporting two of these pMags.

Carl
 
Larry, I fly LOP in cruise but haven’t played with LOP in climb. How do you set LOP climb power and at what altitude do you start leaning?

I take off as normal and at 3K, just pull the mixture back untill I hear the RPM fall off a bit and then set to a known EGT. I then dial in some advance to help with the leaner mixture. You can experiment first at 75% power. Play with the red knob to understand where peak EGT is on your highest EGT cyl. Then you have a reference for setting it. I tend to do LOP climbs more when trying to stretch range, as it slows my climb rate some. During ROP climbs, after 2K AGL, I dial back the mixture to about 100 ROP, to conserve fuel and maximize power. However, at around 8K I need to start pulling some advance as the tables are seeing the lower MAPs and are advancing due to it; This creates excess heat and robs a bit of power.

My injectors are balanced and I would not recommend this approach without that. You don't want any of the cylinders to be at peak or a bit richer, at least when at higher power levels. The GAMI guys have written many articles on this subject if interested.
 
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Thanks for all of the feedback on this. I spoke with Walt today and went ahead and decided to go with the SureFly for my IO-540 on the left side. Just in time to still take advantage of their Oshkosh special which knocked off about $200 from the list price.
 
Been running the Surefly for almost a year. Have it tapped into the manifold line and set for advance. CHTs increased slightly but no issues. Hot starts are easier most of the time. slightly better fuel burn. There is a company, G3x in Colorado where you can create a harness to use auto plugs. I did this. I have no interest in playing with my engine advancement. If you want to tweak your timing and have the ability to adjust, SDS is a good system that allows you to do that.
 
Been running a surefly on the left and regular mag on the right for about 1y and 180h.
I’m running 9:1 so knocked the timing back to 23deg from 25deg pretty early on.
Checked my mag at the same time and it was closer to 28deg which I wasn’t super happy about. You’d think that would be right considering it had a good few hours on the test stand….
I am running the advance.
No issues to report. I plan on putting an auto harness on at some stage and switching to auto plugs too.

The real question will be what to do about the regular mag overhaul as that will come around pretty quickly at this rate. It’ll cost an arm and a leg to get overhauled here so I may well be better off just doing a second surefly.
 
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Thanks for all of the feedback on this. I spoke with Walt today and went ahead and decided to go with the SureFly for my IO-540 on the left side. Just in time to still take advantage of their Oshkosh special which knocked off about $200 from the list price.

****, Really? I asked if there was an Oshkosh discount and was told no, so I had to pay full price. That sucks. I bought it the week of Oshkosh too. I got the Oshkosh discount on the first one I bought last year and waited especially so I could take advantage of it this year.

:(
 
****, Really? I asked if there was an Oshkosh discount and was told no, so I had to pay full price. That sucks. I bought it the week of Oshkosh too. I got the Oshkosh discount on the first one I bought last year and waited especially so I could take advantage of it this year.

:(

I'm a dealer/installer that is the reason I received the discount.
 
Richard, I go back an forth on adding a second Surefly. I did run an extra wire (when I ran wire for the Surefly for my -10) just in case. Dan Horton provided me an easy solution for a second power source since I have a single battery installed. Easy fix with a small 6 amp battery, a diode in the power line from the main battery to charge the aux battery, then the second Surefly runs off the Aux battery. Simple but safe. I have a bendix mag so about 450 dollars for an IRAN. If it was a Slick mag I would do the swap out, but with the Bendix impulse mag on the plane, not as critical.
 
I'm a dealer/installer that is the reason I received the discount.

Good on you - there have to be some perks in the job I guess. :)

As much as I would have liked the discount (US$200 is worth NZ$330 to me, plus tax etc so a saving of NZ$400), the invoice has been paid and you move on.

Out of curiosity, Walt, how many have you installed? Are they popular on certified aircraft or just with the experimental machines?
 
Good on you - there have to be some perks in the job I guess. :)

As much as I would have liked the discount (US$200 is worth NZ$330 to me, plus tax etc so a saving of NZ$400), the invoice has been paid and you move on.

Out of curiosity, Walt, how many have you installed? Are they popular on certified aircraft or just with the experimental machines?

I've done 4 or 5 on Rv's, I don't have time (or desire) to work on certified stuff anymore :D
 
Richard, I go back an forth on adding a second Surefly. I did run an extra wire (when I ran wire for the Surefly for my -10) just in case. Dan Horton provided me an easy solution for a second power source since I have a single battery installed. Easy fix with a small 6 amp battery, a diode in the power line from the main battery to charge the aux battery, then the second Surefly runs off the Aux battery. Simple but safe. I have a bendix mag so about 450 dollars for an IRAN. If it was a Slick mag I would do the swap out, but with the Bendix impulse mag on the plane, not as critical.

Yeah mines a slick so I’ll probably go that route.
I have 2 batteries and 2 alts so it should really just be a matter of one extra wire.
If I was smarter I would have routed the extra during construction. Oh well.
 
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