VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #311  
Old 09-26-2019, 08:11 PM
vlittle's Avatar
vlittle vlittle is offline
 
Join Date: Jan 2005
Location: Victoria, Canada
Posts: 2,226
Default

Quote:
Originally Posted by rv6ejguy View Post
The LOP button is designed to be used when you lean the engine to LOP. This advances the timing (usually 3-5 degrees) and picks up some of the power lost when running lean of peak due to the slower burn rate of the mixture.

Usually see 3-6 knots come back over fixed mag timing, depending on airframe and how far LOP you are.

The amount of advance for LOP is user programmable as are the basic RPM and MAP timing curves. In fact, almost every parameter right down to cranking retard and coil charge times can be changed.

This is the "Last Word" in aircraft EI systems where you want full control of your timing and not a canned curve like most other EIs offer.
I'm not from Missouri (actually from Victoria), but all of these claims about ignition timing made me skeptical. I have an IO540 9.2:1 running one magneto and an Electroair electronic ignition.

I have a switch that cuts off the MAP sensor so I can have baseline timing or advanced timing. That also provided me a convenient spot to intercept the advance signal and massage it with an arduino controller.

So I wrote a sketch that allowed me to add or subtract ignition timing in flight and test some of the claims.

The first test was to try changing the timing with a rich 'best power' mixture at 8500 PA. Stock timing from the Electroair was 33 degrees. I tried between 27 and 38 degrees with no measureable change in airspeed of 201 knots.

The second test was to go LOP around 180 knots and find the best timing. Baseline was 177 knots at 33 degrees and 180 knots at 38 degrees. Yeah!

So, based on this rather elementary test, it looks like the 'canned' curve is a bit too conservative LOP, thus proving Ross's assertion. But I also had to watch CHTs in the climb, so maybe it was too agressive ROP. I can always turn off the advance with the switch, though.

So maybe I can change the shape of my advance curve with some simple programming... less advance when ROP and more advance when LOP. I can figure this out from the Dynon serial data stream.

Vern
__________________
===========
V e r n. ====
=======
RV-9A complete
Harmon Rocket complete
S-21 wings complete
Victoria, BC (Summer)
Chandler, Az (Winter)
Reply With Quote
  #312  
Old 09-26-2019, 09:02 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,694
Default

Your test results mirror typical experience. We haven't found much difference ROP where power seems to be pretty insensitive to timing (though CHTs usually aren't).

LOP, depending on how much and MAP, typical RVs see 3-5 more knots running 32 to 35 degrees total on PV engines. Really high and LOP, some customers claim around 37ish gives best speed.

If you have a long leg, smooth air and some patience to let things stabilize, you can easily see what timing gives best TAS with the CPI/ CPI-2 under various MAP and mixture settings.

I'd be interested in people's feedback from testing.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm


Reply With Quote
  #313  
Old 09-27-2019, 06:05 AM
M McGraw's Avatar
M McGraw M McGraw is offline
 
Join Date: Dec 2012
Location: Greenback, TN
Posts: 530
Default Angle valve engine timing

I have been testing my angle valve engine timing as a function of mixture, RPM, and MAP for about two years. I am very close to what I consider my best curves. I say curves because the most fundamental thing I have learned is that you need a minimum of two curves, one for ROP and another for LOP. My ROP curve covers everything from starting to climb and high power cruise. My LOP curve covers only 2350 to 2700RPM and below 25MAP. Mostly I use it between 18 and 22MAP because of my typical cruise altitudes. I plan to distribute those curves to a friend with a similar engine soon. If he confirms my data we hope to distribute that data to the community.

If you use only one curve you will be too advanced for ROP or not advanced enough for LOP. Both conditions can be acceptable if you set limits on the advance curve, but it is important to understand that too much advance is merely adding heat to the combustion without increased power. A quick summary of my results would be that an angle valve engine and a parallel valve engine respond very differently to advance changes.

All my testing has been done with the SDS EM5 computer which uses the CPI/CPI-2 ignition software, but adds electronic fuel injection.
__________________
Marvin McGraw, 5TN4
RV-14. #140039 Complete
Flight hours: 500+
2020 Dues Paid
The Dues Paid note is a reminder for me
Reply With Quote
  #314  
Old 09-27-2019, 07:43 AM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,694
Default

We welcome your input on the AV engines Marvin.

BTW, the CPI-2 manual has be updated today on the website. We also now list revisions at the bottom of the manual so you can know what was changed.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm


Reply With Quote
  #315  
Old 10-29-2019, 11:43 AM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,694
Default

We've got a number of CPI-2s flying now with more coming soon. We encountered 2 installations where there seemed to be incredible amounts of electrical noise in the airplanes and this was often scrambling the data on the programmer LCD and LEDs. The engines always continued to run fine.

If anyone encounters issues with hyrogliphics or blank lines in the LCD or flashing LED indicators, drop me an email or PM and we'll get this addressed at our expense.

Despite extensive testing during development where we sat the controllers right on top of coil packs while they are firing spark plugs a foot away and wrapping the programmer cable around the spark plug wires with no issues, these 2 installations appear to have more noise present than this "worst case" testing scenario. Both of these problem cases have been rectified now with a programmer mod.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm



Last edited by rv6ejguy : 10-29-2019 at 11:45 AM.
Reply With Quote
  #316  
Old 11-04-2019, 05:45 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,694
Default Magnet Position Values

In case this was missed on our website I thought I'd post it here:

"We've eliminated the need to set Magnet Position with a timing light on Lycoming engines. For engine using the dual pickup, set A ECU Magnet Position to 88 and B to 97. For single pickup installations, set it to 92."

A few new photos of a dual RV-8 install near the bottom of the CPI-2 page uploaded today.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm


Reply With Quote
  #317  
Old 11-28-2019, 03:07 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,694
Default Good Speeds on an RV-8

Kevin Taylor was kind enough to send us a number of photos of his dual CPI-2 install on his RV-8.



This is running LOP. 188 KTAS. Not too shabby on an AV 360.



Kevin also has the new 2 blade Hartzell composite prop which he attributes a number more knots to. He says he's able to hit over 190 KTAS at altitude ROP.
__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm


Reply With Quote
  #318  
Old 12-21-2019, 06:01 PM
rv6ejguy's Avatar
rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,694
Default

We've had a flurry of CPI-2 orders in December. Thank you to every one who has placed an order. Working to get most of these shipped before the end of the year but some of our suppliers are slow in delivering certain parts at this time, mostly due to shipping delays.

Building up several programmers now as time permits. While the basic boards are machine loaded and soldered, there is still quite a bit of hand assembly required with the LEDs, LCDs and keypads into the chassis:

__________________

Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 439.3 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
http://sdsefi.com/cpi2.htm


Reply With Quote
  #319  
Old 02-08-2020, 09:31 PM
Chkaharyer99 Chkaharyer99 is offline
 
Join Date: Oct 2011
Location: Pilot Hill, CA
Posts: 843
Default

I had a very successful test flight today after the installation of my SDS CPI-2, dual channel controller and optional backup battery.

As expected the system works as advertised and I am happy to remove my two slick mags which were almost due for a rebuild.

Big thanks to Ross and Barry at SDS for being available to answer my many questions along the way. The customer service I've received from SDS has been exceptional.

I also want to shout out to Bruce Estes who installed a dual SDS CPI-2 in his RV-6. Bruce gave me lots of guidance along the way. It was also great hearing about his experiences with the system.

Lastly, a big thank you to Lee Ulrich who has an SDS EFI in his RV-7. Lee finished the install, did some fabricating and helped with the timing.
__________________
Charlie
RV-8
Reply With Quote
  #320  
Old 02-09-2020, 12:27 AM
Mike S's Avatar
Mike S Mike S is offline
Senior Curmudgeon
 
Join Date: Sep 2005
Location: Dayton Airpark, NV A34
Posts: 15,268
Default

Quote:
Originally Posted by Chkaharyer99 View Post
I had a very successful test flight today after the installation of my SDS CPI-2 -----
Charlie, congrats on getting the new system up and running.

Now fly on over for a visit.
__________________
Mike Starkey
VAF 909

Rv-10, N210LM.

Flying as of 12/4/2010

Phase 1 done, 2/4/2011

Sold after 240+ wonderful hours of flight.

"Flying the airplane is more important than radioing your plight to a person on the ground incapable of understanding or doing anything about it."
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 10:35 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.