GI-275 with Surefly

[MironV]

Does anyone have experience with Surefly electronic magneto replacement with a GI-275 EIS?
 

I heard somewhere that the GI-275 EIS STC doesn't allow the Surefly. Looking through the install manual the EIS seems to support general P-lead pickups that the Surefly would provide. It's not immediately obvious to me why it would be prohibited to do a drop-in magneto replacement with Surefly.

[Ragsf15e]

1 hour ago, MironV said:

Does anyone have experience with Surefly electronic magneto replacement with a GI-275 EIS?
 

I heard somewhere that the GI-275 EIS STC doesn't allow the Surefly. Looking through the install manual the EIS seems to support general P-lead pickups that the Surefly would provide. It's not immediately obvious to me why it would be prohibited to do a drop-in magneto replacement with Surefly.

I don’t have the gi-275, but I do have the SF with an edm930.  When we installed the SF, we switched the rpm pickup to the right mag.

Depending on how the eis gets tach data, you may or may not have to wire it differently.  There’s some info on the Surefly website and they recommend contacting them.

[qualleyiv]

Working through this issue now with my Surely and GI-275. So far, between calling Garmin (who said it's not supported) and Surefly, I've learned that I need the Tach2 convertor box to support the Surefly's output. What I'm currently trying to determine is whether I also need a mag vent pickup for my existing slick magneto or if there's a better/different way to do this (which is actually what I came here to ask, when I saw this question).

[Ragsf15e]

36 minutes ago, qualleyiv said:

Working through this issue now with my Surely and GI-275. So far, between calling Garmin (who said it's not supported) and Surefly, I've learned that I need the Tach2 convertor box to support the Surefly's output. What I'm currently trying to determine is whether I also need a mag vent pickup for my existing slick magneto or if there's a better/different way to do this (which is actually what I came here to ask, when I saw this question).

Not sure your exact setup, but we just switched my rpm pickup to the remaining mag… is that not possible?

[chriscalandro]

2 hours ago, Ragsf15e said:

Not sure your exact setup, but we just switched my rpm pickup to the remaining mag… is that not possible?

You should have one on each mag. 
 

the electric mags work differently and aren’t compatible with devices that use plead or Hall effect reading techniques. You need the converter box from surefly. 

[Ragsf15e]

9 hours ago, chriscalandro said:

You should have one on each mag. 
 

the electric mags work differently and aren’t compatible with devices that use plead or Hall effect reading techniques. You need the converter box from surefly. 

I don’t doubt you as I’m not a good mechanic, but I have a SF on the left and an edm930.  I was there during the installation of the SF and remember my mechanic saying he was switching the pickup to the right.  Maybebi misheard him?

Are there really 2 rpm pickups feeding the rpm gage?

[chriscalandro]

So how do you read the rpm when you’re not on that mag?

 

im not saying I’m right, but it doesn’t make sense.  The digital instruments read off the p lead or a Hall effect sensor. Neither of which work with the surefly, which requires a converter. 
 

if you don’t have both wired, when on the one not wired you’re going to get 0rpm.  
 

maybe the hall sensor still works? But the original post said PLeads. 

Edited June 23, 2022 by chriscalandro

[Ragsf15e]

59 minutes ago, chriscalandro said:

So how do you read the rpm when you’re not on that mag?

 

im not saying I’m right, but it doesn’t make sense.  The digital instruments read off the p lead or a Hall effect sensor. Neither of which work with the surefly, which requires a converter. 
 

if you don’t have both wired, when on the one not wired you’re going to get 0rpm.  
 

maybe the hall sensor still works? But the original post said PLeads. 

We need a mechanic to chime in, but I don’t have any special converter and I do have rpm running on either mag.  

[Ragsf15e]

In the absence of someone with actual knowledge of this, I found this on kitplanes.  It shows the rpm pickup plugging into the side of the mag.  Jpi also has magnetic pickups for edms.  I’m guessing I have that type.  It seems to only be required on one mag and will pickup rpm whether or not the mag is actually firing because it’s sensing the rotation.  I think this is what my mechanic switched to the other side.  It fits in the mag vent hole/cover.

Tachometer

Traditionally, tachometers have been mechanical devices driven off a dedicated output at the back of the accessory case, but now electronic tachometers are more common, either as standalone units or as part of an engine management system. If the mechanical tachometer drive is not used, a small cap available from aviation supply sources should be installed and safety wired in place. The sensors commonly used for electronic tachometers or EMS units screw into the side of one of the magnetos and connect with standard aviation wire. Electronic ignition systems often have an output for engine rpm built in.

A magnetic tachometer pickup screws into the vent hole in a Slick magneto. When using electronic ignitions, the manufacturer typically provides a lead that can be used for rpm sensing.

[chriscalandro]

Must be. I know I couldn’t use the surefly with the Dynon because they come off the PLead each mag, and I think the G3X does the same. 
 

not without this anyway. 

[Andy95W]

48 minutes ago, Ragsf15e said:

We need a mechanic to chime in, but I don’t have any special converter and I do have rpm running on either mag.  

That type of sensor “sees” the magnet rotating in order to determine the rpm.  The magnet rotates whether the magneto is producing spark or not.

[kortopates]

Not all tachometers or engine monitors use 2 pickups - it depends entirely on what the the monitor uses. For example, E.I, for their RPM R1 and MVP 50 read directly off the p-lead at the ignition switch and tend to connect to both p-leads. While others like EDM, use the hall-effect sensor that screw into the vent of the Mag. They just use one sensor at the mag. A Surelfy installation with the hall-effect sensor is just a matter of moving the sensor to the remaining Mag if needed. But p-lead connection will need a change in isolators or the converter for the Surefly. Luckily Surefly has some options to get it to work, but often with some trial and error involved when the solution is finding the right isolator size.

Edited June 23, 2022 by kortopates

[MisfitSELF]

Somewhat related.  I had my Surefly installed at Top Gun back in May and had an Insight G4 and the legacy (analog needle but uses pulses off the mag) Tach in my 1984 M20J.  I purchased the Tach2 because I suspected I'd need it.  However, Mark tried and tried and could get the Tach signal to work on either device from the Surefly with or without the Tach2.  He tried the different signal outputs from the Tach2 and a variety of resisters working with the Surefly folks.  In the end everyone was stumped. 

We ended up not using the Tach2 and having to purchase and install an EI Tach to replace the legacy Tach and wiring the right mag to the Insight G4.  The EI Tach (which I really don't like the looks of) does pick up the Tach signal from the Surefly without using the Tach2.

Bruce