High CHT, 470 degrees +.

[Shadrach]

18 minutes ago, takair said:

For what it’s worth, I’m just coming up on 100hours on mine.  Small snafu at initial install, but their support was great and performance has been great.  Will be curious what the outcome of this issue is.

Did you do a PIREP after install? Love to know how the angle valve responds to variable ignition timing.

[takair]

27 minutes ago, Shadrach said:

Did you do a PIREP after install? Love to know how the angle valve responds to variable ignition timing.

I did, it’s buried somewhere in here.  At the time I reported more power at altitude (based on higher TAS).  I have 20 degree base timing, so  it may be more noticeable for me than someone with 25.  I also reported slight rise in CHT which I suggested might be a problem for C models.  That said, at the time I did not realize that I had rings going on all cylinders.  Since the top end and break in, I can report even more power based on significant increase in TAS.  I can’t fully explain it since basic compressions were good, as were valves.  As far as fuel flow, I don’t have fuel flow so I can only estimate, but I would estimate 1/2 gallon per hour better or better TAS up higher when the advance kicks in.  Also, my CHTs since break in are now closer to where they were before the Surefly.....so right around 300 through the winter pushing 75%.  Will see how that holds up in summer.

[Ragsf15e]

2 hours ago, Shadrach said:

Did you do a PIREP after install? Love to know how the angle valve responds to variable ignition timing.

I put one on my F in January and like it so far.  Never had trouble starting before, but now it’s almost like a car.

I have not had a noticeable increase in CHTs, but OAT has been really cold this winter, so more to come on that.

 I had pretty extensive performance data from before the change.  About 5 years worth of 3 and 4 way ground speed checks to solve for TAS.  All the speeds included air & ff data from a JPI930.  

So far I’ve been up to 12,500’ with the SF, but the density altitude was only 11,500 due to cold temps.

Rich of peak I do not have measurable gain at any altitude. TAS is equal to or maybe a tiny bit higher than before, but not really measurable.  The fuel flow is pretty much the same.

Lean of peak, I have seen a noticeable increase in TAS. It’s been about 1-4 knots depending on altitude.  Higher gives more increase than before SF.  I would like to get a few more runs at even higher density altitude as the weather warms up before I present my before/after graphs.  Ff lop is similar.  Tough to say if it’s exactly the same but it’s close.

at about 6k and below, theres no change ROP or LOP which makes sense as it’s not advancing timing.

These airplanes are pretty sensitive to weight, cg, density altitude, light turbulence, yaw, etc.  It’s really tough to say the SF improved my lop tas at 12,500’ by 4 knots without a bunch more speed runs, but that’s my preliminary conclusion.

[Andy95W]

3 hours ago, MIm20c said:

I’m sitting here with the plan of sending both off for an iran or buying one of these. This thread has me leaning towards sending them both to a reputable shop. 

I can see that.  This thread has me leaning toward installing the Surefly but not enabling the spark advance.

[Ragsf15e]

39 minutes ago, Andy95W said:

I can see that.  This thread has me leaning toward installing the Surefly but not enabling the spark advance.

The nice thing is you could install it with the advance turned off and see how you like it.  If you get a wild hair and want to turn it on, it’s a dip switch away.

The SOS and mags have obviously been around a long time and work pretty well.  When the SF is working properly, it’s probably a little better, but it’ll take some time to see how reliable it is.

[DXB]

1 hour ago, Ragsf15e said:

The nice thing is you could install it with the advance turned off and see how you like it.  If you get a wild hair and want to turn it on, it’s a dip switch away.

Unfortunately that dip switch requires removing the surefly to access it...

[Guest]

9 hours ago, takair said:

Those must be massive magnetos!  8 outputs?  Can you still get parts?

No parts issues or support issues.  The are the same case size as any other 1200 series magneto, just the wires are closer together.

Clarence

[takair]

7 hours ago, Ragsf15e said:

I put one on my F in January and like it so far.  Never had trouble starting before, but now it’s almost like a car.

I have not had a noticeable increase in CHTs, but OAT has been really cold this winter, so more to come on that.

 I had pretty extensive performance data from before the change.  About 5 years worth of 3 and 4 way ground speed checks to solve for TAS.  All the speeds included air & ff data from a JPI930.  

So far I’ve been up to 12,500’ with the SF, but the density altitude was only 11,500 due to cold temps.

Rich of peak I do not have measurable gain at any altitude. TAS is equal to or maybe a tiny bit higher than before, but not really measurable.  The fuel flow is pretty much the same.

Lean of peak, I have seen a noticeable increase in TAS. It’s been about 1-4 knots depending on altitude.  Higher gives more increase than before SF.  I would like to get a few more runs at even higher density altitude as the weather warms up before I present my before/after graphs.  Ff lop is similar.  Tough to say if it’s exactly the same but it’s close.

at about 6k and below, theres no change ROP or LOP which makes sense as it’s not advancing timing.

These airplanes are pretty sensitive to weight, cg, density altitude, light turbulence, yaw, etc.  It’s really tough to say the SF improved my lop tas at 12,500’ by 4 knots without a bunch more speed runs, but that’s my preliminary conclusion.

I’m curious what your base timing was?  I had done my install in step increments.  First fixed timing....not change, then turned on the advance and saw better TAS above about 6500....in other words, where power normally starts dropping and advance kicks in.  My best TAS didn’t go up, was just able to maintain it for an extra few thousand feet at best power.  Interestingly, my typical MAP numbers to manage speeds also came down about an inch.  I suppose this could be from tapping into the port and throwing off the calibration, but it might be from the advance kicking in at the lower power settings.  Now that I did the top end, performance has really kicked up, so I no longer have a valid point of comparison.  Anyway, wondering if you have 25 degree base timing, which might explain slightly different results?

[Ragsf15e]

3 hours ago, takair said:

I’m curious what your base timing was?  I had done my install in step increments.  First fixed timing....not change, then turned on the advance and saw better TAS above about 6500....in other words, where power normally starts dropping and advance kicks in.  My best TAS didn’t go up, was just able to maintain it for an extra few thousand feet at best power.  Interestingly, my typical MAP numbers to manage speeds also came down about an inch.  I suppose this could be from tapping into the port and throwing off the calibration, but it might be from the advance kicking in at the lower power settings.  Now that I did the top end, performance has really kicked up, so I no longer have a valid point of comparison.  Anyway, wondering if you have 25 degree base timing, which might explain slightly different results?

Nope, mine is set to 20btdc.

If mine is holding speed higher ROP, it’s not enough for me to notice.  So you notice an increase ROP and LOP?

[takair]

1 hour ago, Ragsf15e said:

Nope, mine is set to 20btdc.

If mine is holding speed higher ROP, it’s not enough for me to notice.  So you notice an increase ROP and LOP?

I don’t fly LOP very often so it was ROP.  The most obvious way I noticed a difference is that I have to reduce an additional inch of MAP to stay below the yellow arc. I used to use just under 20”, then it was 19”.   At this power setting, the advance is likely quite active.  I also noticed that climb power longer.  So, max cruise speed wasn’t higher, it was that I was able to do it at higher altitude.  With the new jugs, it is like a different airplane.  Didn’t know what I was missing.  Don’t get me wrong, I didn’t have expectations of significant increase, but under some of these conditions it certainly changed things.  Wish I had fuel flow, that would be the most telling.  I keep putting it off...

[Shadrach]

59 minutes ago, takair said:

I don’t fly LOP very often so it was ROP.  The most obvious way I noticed a difference is that I have to reduce an additional inch of MAP to stay below the yellow arc. I used to use just under 20”, then it was 19”.   At this power setting, the advance is likely quite active.  I also noticed that climb power longer.  So, max cruise speed wasn’t higher, it was that I was able to do it at higher altitude.  With the new jugs, it is like a different airplane.  Didn’t know what I was missing.  Don’t get me wrong, I didn’t have expectations of significant increase, but under some of these conditions it certainly changed things.  Wish I had fuel flow, that would be the most telling.  I keep putting it off...

I have flown in both 20° and 25° but there is no way to really verify all other things equal.  My experience is that the difference in speed was near enough as to make no difference. Climb on the other hand seemed to be noticeably improved.   I have never understood how lycoming could get away with running two different ignition settings but still call the engines the same horsepower.  Someone once told me that the difference in engine performance was unnoticeable. They also claimed that the retarded timing measurably reduces CHTs. Talk about having it both ways...apparently there is a free lunch.

[carusoam]

I think Byron May have done a good job of defining performance differences for his J between 20 and 25° BTDC....

We learned who was able and what it took to make the change...

Increased timing leads to hotter CHTs which would be more noticeable in July in Houston... around the TPA...

Decreased timing leads to hotter EGTs which is tough on exhaust parts as the flames are still burning on the way by...

With electronic ignition, it would be great if we could really advance them with full knowledge of what we are doing...

Be ready for the costs of making a memory mistake...

PP thoughts only, not a mechanic...

Best regards,

-a-

[Shadrach]

25 minutes ago, carusoam said:

I think Byron May have done a good job of defining performance differences for his J between 20 and 25° BTDC....

We learned who was able and what it took to make the change...

Increased timing leads to hotter CHTs which would be more noticeable in July in Houston... around the TPA...

Decreased timing leads to hotter EGTs which is tough on exhaust parts as the flames are still burning on the way by...

With electronic ignition, it would be great if we could really advance them with full knowledge of what we are doing...

Be ready for the costs of making a memory mistake...

PP thoughts only, not a mechanic...

Best regards,

-a-

I have a 25° engine. My CHT’s in level flight are almost never above 340 even in the mid Atlantic August. I’m the winter it’s a struggle to stay above 300. EGT’s all peak in the mid 1400 to low 1500s. I don’t see how you have two identical engines rated at the same power but one running 25% more  advance

Edited April 21, 2020 by Shadrach

[carusoam]

How they rated the engine’s power back in the day has mostly been a mystery...
 

In cars... it took going to the drag strip to measure performance... even there it was quite dynamic under extended acceleration...

Show you a race car in disguise, and tell you you bought the same thing...

Truth in advertising laws came from somewhere... 

As time marches on...

the marketing teams are under a bit of pressure to use actual data...

Not only do people measure performance data every flight... they can download it and share it widely...

Simply changing the timing, definitely changes the useable HP... as does porting and polishing...

In modern cars... loping around in cruise, LOP... their timing is something like 60°BTDC... Way outside the redbox of 65% bhp...

I can net 30mpg in a 90s C4 Chevy... highest gear, lowest throttle position... maintaining rpm...

Omitting the whole truth seemed to be normal behavior for some machine builders... and large corporations...

That’s getting tougher to hide...

And we are better for it...

With MS... we are incredibly well educated consumers... 

Best regards,

-a-

[Shadrach]

13 minutes ago, carusoam said:

How they rated the engine’s power back in the day has mostly been a mystery...
 

In cars... it took going to the drag strip to measure performance... even there it was quite dynamic under extended acceleration...

Show you a race car in disguise, and tell you you bought the same thing...

Truth in advertising laws came from somewhere... 

As time marches on...

the marketing teams are under a bit of pressure to use actual data...

Not only do people measure performance data every flight... they can download it and share it widely...

Simply changing the timing, definitely changes the useable HP... as does porting and polishing...

In modern cars... loping around in cruise, LOP... their timing is something like 60°BTDC... Way outside the redbox of 65% bhp...

I can net 30mpg in a 90s C4 Chevy... highest gear, lowest throttle position... maintaining rpm...

Omitting the whole truth seemed to be normal behavior for some machine builders... and large corporations...

That’s getting tougher to hide...

And we are better for it...

With MS... we are incredibly well educated consumers... 

Best regards,

-a-

60 is a lot. I can see real time parameters on my cheap Autotel OBD sensor, 40BTDC is about the max I’ve seen but your point is well taken.

Edited April 21, 2020 by Shadrach