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Single electronic ignition

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glcasey(at)adelphia.net
Guest

Posted: Wed Jun 28, 2006 5:02 am Post subject: Single electronic ignition

I have a IO-540 parallel-valve with 10:1 compression, a single Slick  

mag and one Lightspeed ignition.  I now have about 5 flight hours on  

the engine.  The engine was set up with 25 degrees timing on both  

ignitions, but I was worried about peak cylinder pressures and  

retarded the mag to about 21.5 degrees.  Runups are a problem in that  

there is a slight drop going to the electronic ignition (I expected  

that), but a drop of maybe 300 rpm from 1700 on the mag and running  

on the mag almost always misfires until I run lean for several  

seconds to dry out the plugs.  The misfire situation is getting  

better, I assume because the engine is breaking in and using less oil  

and partly because I'm doing less ground running than before.  I'm  

wondering if the large mag drop is normal, possibly because the  

Lightspeed is giving quite a bit of advance during runup because of  

the low manifold pressure (I forgot to read the MAP during runup).   

Doe anyone know what the advance "curve" looks like for the  

Lightspeed?  I understand others have asked for an official answer  

and it was supposedly "proprietary", but I also understand you can  

get a readout from Lightspeed that gives the actual advance.  All one  

would have to do is plot the displayed number against rpm and MAP to  

extract the algorithm.  Anyone done that?  If I wanted to reduce the  

advance on the Lightspeed by maybe 5 degrees is there a simple way to  

do that?  I don't have any travel in that direction on the pickup  

plate and I don't want to retard the cranking advance.



Gary Casey

flyv35b(at)ashcreekwirele
Guest

Posted: Wed Jun 28, 2006 5:33 am Post subject: Single electronic ignition

Very interesting comments and questions.  I would be interested in knowing 

the answers when you find out some more info.



How are you CHT's and oil temperature with the 10:1 pistons?   What kind of 

plane is the engine in?



Cliff  A&P/IA

---

jrccea(at)bellsouth.net
Guest

Posted: Wed Jun 28, 2006 6:00 am Post subject: Single electronic ignition

To me, a 300 rpm drop sounds about normal for a mag set to 21.5 degrees. 

Have you thought about setting it back to 25, in order to reduce the drop 

and the misfiring?



---

glasair(at)epix.net
Guest

Posted: Wed Jun 28, 2006 6:06 am Post subject: Single electronic ignition

Gary,

    What aircraft is your Lightspeed system in?

I have a Glasair III , IO-540K1A5 angle valve with Klaus' system replacing 

one mag for a period of time as I built the courage to install both 

Lightspeed systems. One electronic unit works better than none. Two are far 

superior in all parameters. I now have about six or eight years and several 

hundred hours on Klaus' units and have found them to be totally reliable and 

trouble free.

    Don't mean to sound like a salesman but if you want to contact me by 

phone I would be glad to discuss this topic.

Regards,

Ken Johnson

---

glcasey(at)adelphia.net
Guest

Posted: Wed Jun 28, 2006 6:22 am Post subject: Single electronic ignition

I forgot to mention - one characteristic of this setup is that when  

going LOP at 10% less fuel flow than at peak the EGT's will drop less  

than 50 degrees(F) before they start going up again.  At that time  

the engine is obviously on the ragged edge and will start to run very  

rough, occasionally even back-firing.  I haven't seen - or haven't  

noticed - this upward EGT trend and such a sharp lean limit on other  

engines.  Is it because of the higher compression?  Should I worry?



Gary Casey



On Jun 28, 2006, at 5:57 AM, Gary Casey wrote:



 	  Quote: 	
		   I have a IO-540 parallel-valve with 10:1 compression, a single  

 Slick mag and one Lightspeed ignition.  I now have about 5 flight  

 hours on the engine.  The engine was set up with 25 degrees timing  

 on both ignitions, but I was worried about peak cylinder pressures  

 and retarded the mag to about 21.5 degrees.  Runups are a problem  

 in that there is a slight drop going to the electronic ignition (I  

 expected that), but a drop of maybe 300 rpm from 1700 on the mag  

 and running on the mag almost always misfires until I run lean for  

 several seconds to dry out the plugs.  The misfire situation is  

 getting better, I assume because the engine is breaking in and  

 using less oil and partly because I'm doing less ground running  

 than before.  I'm wondering if the large mag drop is normal,  

 possibly because the Lightspeed is giving quite a bit of advance  

 during runup because of the low manifold pressure (I forgot to read  

 the MAP during runup).  Doe anyone know what the advance "curve"  

 looks like for the Lightspeed?  I understand others have asked for  

 an official answer and it was supposedly "proprietary", but I also  

 understand you can get a readout from Lightspeed that gives the  

 actual advance.  All one would have to do is plot the displayed  

 number against rpm and MAP to extract the algorithm.  Anyone done  

 that?  If I wanted to reduce the advance on the Lightspeed by maybe  

 5 degrees is there a simple way to do that?  I don't have any  

 travel in that direction on the pickup plate and I don't want to  

 retard the cranking advance.



 Gary Casey

BPA(at)bpaengines.com
Guest

Posted: Wed Jun 28, 2006 6:30 am Post subject: Single electronic ignition

Gary:



Have you contacted your engine builder?  They should be able to provide

you with detailed information and help trouble shoot your concerns.



Regards,



Allen Barrett

Barrett Precision Engines, Inc.

2870-B N. Sheridan Rd.

Tulsa, OK  74115

(918) 835-1089 phone

(918) 835-1754 fax

www.barrettprecisionengines.com



"Visit us at Airventure 2006, Bldg. C, Booth 3025"



DO NOT ARCHIVE



--

lors01(at)msn.com
Guest

Posted: Wed Jun 28, 2006 6:36 am Post subject: Single electronic ignition

<?xml:namespace prefix="v" /><?xml:namespace prefix="o" /><![endif]-->  Don't blame you for wanting to know as much as you can about your aircraft  systems and hope this does not come off as condescending.  Having said  that, I would encourage you to follow the manufacturers' recommendation on  setting up the system. 

  

 I make EFI/Ignition engine controllers (for auto engine conversions) and  the algorithms for ignition timing can be devilishly difficult to describe in a  reasonable amount of time.  There are so many if, ands, or buts  that only a spreadsheet can accurately illustrate the timing.   It's not a simple curve, at least not in a sophisticated ignition  system.  

  

 Don't take this as an indication that I know anything about the Lightspeed  system, I don't.  But I have had several builders come close to damaging  their engines by trying to second guess what my controllers are  doing.  If you are going to entrust your machine to a manufacturer's  widget, you might as well follow the instructions.

  

 I (and Lightspeed) ought to provide the spreadsheet that illustrates the  timing curve and I intend to do that as soon as I find the time.  The  number of different engines that I make controllers for has grown to around  20 (timing is different on all of them) so it won't be easy.

  

 Tracy Crook

 [quote]   ---

cberland(at)systems3.net
Guest

Posted: Wed Jun 28, 2006 7:22 am Post subject: Single electronic ignition

Gary, I suspect that the mag is misfiring as you lean causing the burn

time to increase and therefore the exhaust temps to climb as you

continue to lean rather than the expected further temp decrease.  I

would be more inclined to set both ignitions at 22 or 23 deg BTDC.  By

setting the mag retarded it must fire against a slightly higher

combustion chamber pressure due to the electronic ign has already fired

and the pressure is rising.  The mag is already being challenged by the

10 to 1 CR and LOP operation.

Craig Berland

I forgot to mention - one characteristic of this setup is that when

going LOP at 10% less fuel flow than at peak the EGT's will drop less

than 50 degrees(F) before they start going up again.  At that time the

engine is obviously on the ragged edge and will start to run very rough,

occasionally even back-firing.  I haven't seen - or haven't noticed -

this upward EGT trend and such a sharp lean limit on other engines.  Is

it because of the higher compression?  Should I worry?



Gary Casey



On Jun 28, 2006, at 5:57 AM, Gary Casey wrote:



 	  Quote: 	
		   I have a IO-540 parallel-valve with 10:1 compression, a single Slick 

 mag and one Lightspeed ignition.  I now have about 5 flight hours on 

 the engine.  The engine was set up with 25 degrees timing on both 

 ignitions, but I was worried about peak cylinder pressures and 

 retarded the mag to about 21.5 degrees.  Runups are a problem in that 

 there is a slight drop going to the electronic ignition (I expected 

 that), but a drop of maybe 300 rpm from 1700 on the mag and running on


	


 	  Quote: 	
		   the mag almost always misfires until I run lean for several seconds to


	


 	  Quote: 	
		   dry out the plugs.  The misfire situation is getting better, I assume 

 because the engine is breaking in and using less oil and partly 

 because I'm doing less ground running than before.  I'm wondering if 

 the large mag drop is normal, possibly because the Lightspeed is 

 giving quite a bit of advance during runup because of the low manifold


	


 	  Quote: 	
		   pressure (I forgot to read the MAP during runup).  Doe anyone know 

 what the advance "curve"

 looks like for the Lightspeed?  I understand others have asked for an 

 official answer and it was supposedly "proprietary", but I also 

 understand you can get a readout from Lightspeed that gives the actual


	


 	  Quote: 	
		   advance.  All one would have to do is plot the displayed number 

 against rpm and MAP to extract the algorithm.  Anyone done that?  If I


	


 	  Quote: 	
		   wanted to reduce the advance on the Lightspeed by maybe

 5 degrees is there a simple way to do that?  I don't have any travel 

 in that direction on the pickup plate and I don't want to retard the 

 cranking advance.



 Gary Casey

s_korney(at)hotmail.com
Guest

Posted: Wed Jun 28, 2006 9:52 am Post subject: Single electronic ignition

Gary...



One malfunction in the MAP sensor, and your engine could be toasted... I 

recommend you run the slick mag at 23 degrees for the 10:1 compression... 

Your light speed could be as much as 40 degrees at run-up... No wonder there 

is such a difference in drop-off in rpm's...



Best... Steve



----Original Message Follows----

Reply-To: engines-list(at)matronics.com






I have a IO-540 parallel-valve with 10:1 compression, a single Slick  mag 

and one Lightspeed ignition.  I now have about 5 flight hours on  the 

engine.  The engine was set up with 25 degrees timing on both  ignitions, 

but I was worried about peak cylinder pressures and  retarded the mag to 

about 21.5 degrees.  Runups are a problem in that  there is a slight drop 

going to the electronic ignition (I expected  that), but a drop of maybe 300 

rpm from 1700 on the mag and running  on the mag almost always misfires 

until I run lean for several  seconds to dry out the plugs.  The misfire 

situation is getting  better, I assume because the engine is breaking in and 

using less oil  and partly because I'm doing less ground running than 

before.  I'm  wondering if the large mag drop is normal, possibly because 

the  Lightspeed is giving quite a bit of advance during runup because of  

the low manifold pressure (I forgot to read the MAP during runup).   Doe 

anyone know what the advance "curve" looks like for the  Lightspeed?  I 

understand others have asked for an official answer  and it was supposedly 

"proprietary", but I also understand you can  get a readout from Lightspeed 

that gives the actual advance.  All one  would have to do is plot the 

displayed number against rpm and MAP to  extract the algorithm.  Anyone done 

that?  If I wanted to reduce the  advance on the Lightspeed by maybe 5 

degrees is there a simple way to  do that?  I don't have any travel in that 

direction on the pickup  plate and I don't want to retard the cranking 

advance.



Gary Casey



http://www.matronics.com/Navigator?Engines-List

http://wiki.matronics.com

s_korney(at)hotmail.com
Guest

Posted: Wed Jun 28, 2006 9:55 am Post subject: Single electronic ignition

If your going to run your engine lean of peak at high altitude, you should 

have two electronic ignitions...



Best... Steve



----Original Message Follows----

Reply-To: engines-list(at)matronics.com






I forgot to mention - one characteristic of this setup is that when  going 

LOP at 10% less fuel flow than at peak the EGT's will drop less  than 50 

degrees(F) before they start going up again.  At that time  the engine is 

obviously on the ragged edge and will start to run very  rough, occasionally 

even back-firing.  I haven't seen - or haven't  noticed - this upward EGT 

trend and such a sharp lean limit on other  engines.  Is it because of the 

higher compression?  Should I worry?



Gary Casey



On Jun 28, 2006, at 5:57 AM, Gary Casey wrote:



 	  Quote: 	
		  I have a IO-540 parallel-valve with 10:1 compression, a single  Slick mag 

and one Lightspeed ignition.  I now have about 5 flight  hours on the 

engine.  The engine was set up with 25 degrees timing  on both ignitions, 

but I was worried about peak cylinder pressures  and retarded the mag to 

about 21.5 degrees.  Runups are a problem  in that there is a slight drop 

going to the electronic ignition (I  expected that), but a drop of maybe 

300 rpm from 1700 on the mag  and running on the mag almost always misfires 

until I run lean for  several seconds to dry out the plugs.  The misfire 

situation is  getting better, I assume because the engine is breaking in 

and  using less oil and partly because I'm doing less ground running  than 

before.  I'm wondering if the large mag drop is normal,  possibly because 

the Lightspeed is giving quite a bit of advance  during runup because of 

the low manifold pressure (I forgot to read  the MAP during runup).  Doe 

anyone know what the advance "curve"  looks like for the Lightspeed?  I 

understand others have asked for  an official answer and it was supposedly 

"proprietary", but I also  understand you can get a readout from Lightspeed 

that gives the  actual advance.  All one would have to do is plot the 

displayed  number against rpm and MAP to extract the algorithm.  Anyone 

done  that?  If I wanted to reduce the advance on the Lightspeed by maybe  

5 degrees is there a simple way to do that?  I don't have any  travel in 

that direction on the pickup plate and I don't want to  retard the cranking 

advance.



Gary Casey


	




http://www.matronics.com/Navigator?Engines-List

http://wiki.matronics.com

s_korney(at)hotmail.com
Guest

Posted: Wed Jun 28, 2006 10:07 am Post subject: Single electronic ignition

Craig...



You are right about......



"I would be more inclined to set both ignitions at 22 or 23 deg

BTDC.  By setting the mag retarded it must fire against a slightly higher

combustion chamber pressure due to the electronic ign has

already fired and the pressure is rising.  The mag is already being 

challenged

by the 10 to 1 CR and LOP operation."



But, that doesn't happen on run-up... The EI is turned off...

Best... Steve



----Original Message Follows----

Reply-To: engines-list(at)matronics.com




Gary, I suspect that the mag is misfiring as you lean causing the burn

time to increase and therefore the exhaust temps to climb as you

continue to lean rather than the expected further temp decrease.  I

would be more inclined to set both ignitions at 22 or 23 deg BTDC.  By

setting the mag retarded it must fire against a slightly higher

combustion chamber pressure due to the electronic ign has already fired

and the pressure is rising.  The mag is already being challenged by the

10 to 1 CR and LOP operation.

Craig Berland

I forgot to mention - one characteristic of this setup is that when

going LOP at 10% less fuel flow than at peak the EGT's will drop less

than 50 degrees(F) before they start going up again.  At that time the

engine is obviously on the ragged edge and will start to run very rough,

occasionally even back-firing.  I haven't seen - or haven't noticed -

this upward EGT trend and such a sharp lean limit on other engines.  Is

it because of the higher compression?  Should I worry?



Gary Casey



On Jun 28, 2006, at 5:57 AM, Gary Casey wrote:



 > I have a IO-540 parallel-valve with 10:1 compression, a single Slick

 > mag and one Lightspeed ignition.  I now have about 5 flight hours on

 > the engine.  The engine was set up with 25 degrees timing on both

 > ignitions, but I was worried about peak cylinder pressures and

 > retarded the mag to about 21.5 degrees.  Runups are a problem in that

 > there is a slight drop going to the electronic ignition (I expected

 > that), but a drop of maybe 300 rpm from 1700 on the mag and running on



 > the mag almost always misfires until I run lean for several seconds to



 > dry out the plugs.  The misfire situation is getting better, I assume

 > because the engine is breaking in and using less oil and partly

 > because I'm doing less ground running than before.  I'm wondering if

 > the large mag drop is normal, possibly because the Lightspeed is

 > giving quite a bit of advance during runup because of the low manifold



 > pressure (I forgot to read the MAP during runup).  Doe anyone know

 > what the advance "curve"

 > looks like for the Lightspeed?  I understand others have asked for an

 > official answer and it was supposedly "proprietary", but I also

 > understand you can get a readout from Lightspeed that gives the actual



 > advance.  All one would have to do is plot the displayed number

 > against rpm and MAP to extract the algorithm.  Anyone done that?  If I



 > wanted to reduce the advance on the Lightspeed by maybe

 > 5 degrees is there a simple way to do that?  I don't have any travel

 > in that direction on the pickup plate and I don't want to retard the

 > cranking advance.

 >

 > Gary Casey

jrdial(at)hal-pc.org
Guest

Posted: Wed Jun 28, 2006 12:05 pm Post subject: Single electronic ignition

My engine is an XP-360 and I always taxi and idle on the ground

with the mixture at almost idle cut off. It won't hurt your engine and

the plugs will stay clean. I am flying 200 hours a year and the plugs

are clean when I pull them once a year. I have the same set up you have

but my mag is set at factory setting of 25 degrees. I have great

performance with the Lightspeed system and I received excellent customer

service on some initial questions to Klaus. I get no drop during run up

on the Lightspeed and about 50 RPM on the mag.

	Good luck



--

glcasey(at)adelphia.net
Guest

Posted: Thu Jun 29, 2006 5:38 am Post subject: Single electronic ignition

Thanks to all for the most excellent replies.  Before building the  

engine I surveyed the internet for comments on 1 vs 2 electronic  

systems.  The benefits when using just one system with advance  

capability varied from 1/2 to 80% of what you can get with 2  

systems.  For simplicity I went with one.  If I now went with 2 I  

think the easiest backup system would be a small battery powering the  

second ignition and charged through a diode.  Some warning would have  

to be given if the primary system quit and then I would have some  

finite time available on the backup battery.



Gary Casey

Lancair ES N224SG



On Jun 28, 2006, at 11:56 PM, Engines-List Digest Server wrote:

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