I took a quick look at the docs on their website. It appeared to me that it's like most other EIs in that it would require a redundant power source? Or is something built into it like the PMag?
I spoke with Les Staples at SnF. The sim requires around 8 vdc to fire. If you only put one on then your mag is the redundancy. It uses the same wires and cap from Slick so it is a very simple install. I will likely add one when my mags need overhauled just for the efficiency and reliability.
OK, so if you had two of them, you'd need some sort of redundant external power supply?
Yes, but what would be the gain in performance over just having one? Again, the KISS principle comes into play...
Yes, but what would be the gain in performance over just having one?
Again, the KISS principle comes into play...
In the case of an angle valve, I suspect one Surefly would be just about right.
The stated advance is base plus 13. In the case of a dual Surefly install with base 20 timing, 33 BTDC would be too much. However, one mag at 20 and one Surefly would probably put effective timing in the sweet spot.
Illustrating yet again the fallacy of a "one size fits all" curve.
Any electronic ignition system that burns the mixture more efficiently is going to highlight any deficiencies within your powerplant system. The CHT's will run slightly higher (10 degrees, below 25" MP) as you are extracting more BTU's from the fuel.
I think I am more of the target audience than those who want complete control.
I really think the average owner would be better served with a fixed timing EI...all the energy, but no advance. It would provide the starting and lean operation advantages, but would not cripple climb due to CHT and oil temp concerns. If it's down a few knots, just climb an extra 2000 feet. Easy to do when your CHTs are low.
...Mike would be an optimizer; best performance above all. If "best" includes a lot of advance, then "all" includes higher CHT and higher mechanical stress. It's a choice, and I'm not knocking it. I simply prefer low CHT and reduced mechanical stress, even if I accept slightly less power to get it...
....Here's the thing; spark energy and spark timing are two different issues. They tend to get balled together, which is a shame. I really think the average owner would be better served with a fixed timing EI...all the energy, but no advance. It would provide the starting and lean operation advantages, but would not cripple climb due to CHT and oil temp concerns...
I think Surefly has a fixed timing mode.
Not so fast.
Now put yourself in the shoes of the average Joe...
...He doesn't care if he squeezes out three more knots...
I think I?m near to Dan?s camp. Running Plasma III and a Pmag. I could get a fairly non advanced spark if I disconnect the manifold tube from these systems, correct?
Seems like the "average Joe" VAFer would gladly trade a few hours of some some tuning in exchange, don't you think?
I think the fact that the majority of us RVers still run mags is a testament to the contrary.
I built my plane, and I have a master's degree in engineering. I am confident that if I wanted to become an expert in engine timing and tweak every single ounce of performance out of my ignition, I could, eventually. But I also wouldn't half-@$$ it, because my engine is too important to me. And since I don't have the time or desire to go all-in on ignition systems, I just want what I stated previously: better performance and better reliability than a mag, which it sounds like the Surefly, maybe even with a fixed curve, could deliver. Also, I am (gasp) carbureted, so max efficiency is already out of the question.
Maybe it is either "right" or "not right", but if so, 99.99% of planes have been flying around "not right" since the dawn of reciprocating engines, so I won't feel too bad about it.
Don't get me wrong, I love the fact that there are smart, passionate people like you guys leading the way for us, and one day I'd love to have the time to join you, but until then it's all about simplicity and reliability for me. I don't need to brag about performance, I can barely get in the air with my 150 horses
Chris
I think the fact that the majority of us RVers still run mags is a testament to the contrary.
Maybe it is either "right" or "not right", but if so, 99.99% of planes have been flying around "not right" since the dawn of reciprocating engines, so I won't feel too bad about it.
Don't get me wrong, I love the fact that there are smart, passionate people like you guys leading the way for us, and one day I'd love to have the time to join you, but until then it's all about simplicity and reliability for me. I don't need to brag about performance, I can barely get in the air with my 150 horses
Chris
What is the advance curve of the LSE Plasma III?
Thx.
...The Surefly is not competing with Pmag and other user adjustable EI's...
...I would argue that the curve is not aggressive...
...So, if you want an EI that you can be loaded with a curve that worked for someone else, and then test fly it to its optimum, PMag is the system for you. Great guys and a great product...
Surefly might be a slight step up in some circumstances, but that will require analysis and test.
Note the engine control computer in your automobile shifts the advance map in lockstep with fuel mixture; it's invisible to the operator. Unfortunately, none of the currently available ignitions for aircraft have that capability. The advance schedules are biased toward LOP operation, and are generally a little too advanced for ROP climb.
...at altitude, the parallel valve engines respond to more and more advance with more and more speed, and no one seems to have found an absolute performance limit (the practical limit is CHT rise). The practical result was a trend toward more advance being incorporated into electronic ignitions...
...Among consumers, the resulting CHT increases during ROP climb have become synonymous with EI....
Let's make sure the readership understands the proper context of "practical limit".
But point taken: It's impossible to create a canned curve with enough breadth to handle every possible use case. And the larger the canned curve, the higher the probability that someone with an edge case is going to get stung by a dangerous condition.
But you have to go to Ross to buy one.
....my total advance with the LOP switch is set around 27-28 degrees. It seemed to be diminishing returns after that.
Ok, so quit arguing against an absolutely safe alternative, one requiring no deep knowledge or test pilot skills...fixed timing at standard Lycoming values...
What is obvious from these comments is that the internet experts haven?t bothered to look at the Surefly timing schedule. It is dependent on RPM AND MP. It would take extreme conditions for it to get to 38 BTDC.
As someone with over 40 years in aerospace as a airline mechanic, technical writer (translating engineering into English) working closely with engineers and as a freelance consultant and building the X47B prototype many ?facts? I see make me cringe.
2700 RPM at any altitude over 9000. Not extreme for a fixed pitch RV.
.....
To be more precise for a standard Lycoming, it appears to be 36.5 degrees at 2700 rpm
However, it will advance up to 38 degrees once your are in the detonation safe zone below 25" manifold pressure.
Sounds like you guys have it all figured out.
To be more precise for a standard Lycoming, it appears to be 36.5 degrees at 2700 rpm
https://docs.wixstatic.com/ugd/712b87_19a81ce5b1eb45f3b07af440a99b37e8.pdf