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  #1  
Old 01-30-2016, 03:03 PM
carrollcw's Avatar
carrollcw carrollcw is offline
 
Join Date: Jan 2012
Location: Friendswood, TX
Posts: 193
Default My GAMI Spread is now ZERO!!!

For those who have not seen my other thread about uneven airflow, I figured I repost a rundown of what has happened to get my GAMI to zero.

I have a new Titan IOX370 running dual EFII ignition and injection with vertical induction. With the stock setup, I had a GAMI spread of 1.3! In trying to determine how to reduce the GAMI spread, I realized (with the help of my neighbor Rusty Crawford) the root cause of the high spread was uneven airflow between the 1/3 cylinders compared to the 2/4 cylinders. This was determined because when ROP, 1/3 had the hottest CHT's, but when LOP they were the coolest (and I verified it was not due to injector imbalance).

So, after some research, it was recommended to me to swap my ECI sump out with a Superior sump. Apparently the Superior sump is known to have better airflow. So, I sucked it up and swapped the sump out, and to my surprise it made absolutely no difference in my temperatures. So now what?

Luckily, Rusty told me that for the past few years he had been working with Ross at SDS on technology where each individual injector could be tuned. This would be a precise way to handle my airflow problem and get me theoretically to a GAMI of zero. Well, the guys at SDS finished the new circuit board and sent it to Rusty for installation in his -7, but Rusty's -7 was down for painting. So, Rusty asked if I'd like to be the first to try out the new technology! How could I refuse?!?!

So, with his help, the modification to my existing EFII setup only took a few hours and was relatively simple.

As the pics below show, after 45 seconds of tuning, I went from a GAMI spread of 1.3 to a GAMI spread of 0. Engine runs smooth all the way to about 200 deg LOP where as before I could only get to about 80 deg LOP since before when 80 LOP, cylinders 1/3 were at about 200 deg LOP.

Another benefit is now I have a clear picture of which cylinders I need to focus on for better cooling. Before I would have thought it was 1/3, but actually I need to work on 2/4 first.

Plus, now I am getting more average power with less wasted fuel since all of the cylinders are making optimum power.

Amazing work by the SDS team and Rusty Crawford. This has been many years in the making! I feel so lucky to have gotten to try this out for them!!!

Picture 1 - Leaning to LOP before the tuning - GAMI approx 1.3, notice large EGT spread, also notice 1/3 had highest CHT's and EGTs' when ROP, but coldest when LOP
Picture 2 - Leaning to LOP after the tuning - GAMI 0, notice how 2/4 always have hottest CHT's now.
Picture 3 - ROP climb before tuning - Large EGT spread
Picture 4 - ROP climb after tuning

Picture 1


Picture 2


Picture 3


Picture 4
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RV-7 Flying Since March 2015
N412HC
Titan IOX-370
SDS Tunable Injectors
EFII Dual Ignition and Fuel Injection
Garmin G3X Touch
Whirl Wind 200RV Prop
7XS0 Polly Ranch Airpark, Friendswood, TX
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  #2  
Old 01-30-2016, 03:12 PM
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carrollcw carrollcw is offline
 
Join Date: Jan 2012
Location: Friendswood, TX
Posts: 193
Default

Heres a couple more pics:

ROP Before


ROP After


LOP After
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RV-7 Flying Since March 2015
N412HC
Titan IOX-370
SDS Tunable Injectors
EFII Dual Ignition and Fuel Injection
Garmin G3X Touch
Whirl Wind 200RV Prop
7XS0 Polly Ranch Airpark, Friendswood, TX
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  #3  
Old 01-30-2016, 03:52 PM
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rmartingt rmartingt is offline
 
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Location: Savannah, GA
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Default

Now that you have it tuned, are you finding that just leaving that tuning in place works well across all power settings, or do you reset it when not going LOP?
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  #4  
Old 01-30-2016, 04:57 PM
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carrollcw carrollcw is offline
 
Join Date: Jan 2012
Location: Friendswood, TX
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Default

Quote:
Originally Posted by rmartingt View Post
Now that you have it tuned, are you finding that just leaving that tuning in place works well across all power settings, or do you reset it when not going LOP?
No, you tune it once and leave it alone.

And RE the fuel pressure, that is what is recommended for the EFII fuel injection system.
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RV-7 Flying Since March 2015
N412HC
Titan IOX-370
SDS Tunable Injectors
EFII Dual Ignition and Fuel Injection
Garmin G3X Touch
Whirl Wind 200RV Prop
7XS0 Polly Ranch Airpark, Friendswood, TX
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  #5  
Old 01-13-2017, 06:35 PM
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johnbright johnbright is offline
 
Join Date: Aug 2010
Location: Newport News, Va
Posts: 389
Default

Clark Carroll said: "So, with his help, the modification to my existing EFII setup only took a few hours and was relatively simple."

Hi Clark... question... what does the modification to your dual EFII entail in order to adjust fuel flow cylinder by cylinder?
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  #6  
Old 01-13-2017, 06:55 PM
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rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
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Default

Quote:
Originally Posted by johnbright View Post
Clark Carroll said: "So, with his help, the modification to my existing EFII setup only took a few hours and was relatively simple."

Hi Clark... question... what does the modification to your dual EFII entail in order to adjust fuel flow cylinder by cylinder?
You'd need a lot of new wiring and hardware in addition to ECU reflashes to have this capability. You'd have to have EM-5 boards. Can't be done with EM-4 boards.
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Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 450.6 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
https://www.youtube.com/channel/UCiy...g2GvQfelECCGoQ


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  #7  
Old 01-13-2017, 07:30 PM
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johnbright johnbright is offline
 
Join Date: Aug 2010
Location: Newport News, Va
Posts: 389
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Hi Ross,

I'm looking at a new install, not an upgrade. I don't know if EFII uses EM-4 or EM-5. I guess EM-4 is no longer produced?

Last edited by johnbright : 01-13-2017 at 07:32 PM.
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  #8  
Old 01-13-2017, 07:33 PM
titanhank titanhank is offline
 
Join Date: Aug 2007
Location: Friendswood, Tx
Posts: 476
Default

Nice job. I always knew your plane was fast.
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  #9  
Old 01-14-2017, 09:38 AM
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rv6ejguy rv6ejguy is offline
 
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Location: Calgary, Canada
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Quote:
Originally Posted by johnbright View Post
Hi Ross,

I'm looking at a new install, not an upgrade. I don't know if EFII uses EM-4 or EM-5. I guess EM-4 is no longer produced?
EFII does not offer the fuel trim function nor some of the other SDS features. If you go with SDS, you can order all available options- Fuel trim, LOP switch, dual access programmer and PC data logging.
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Ross Farnham, Calgary, Alberta
Turbo Subaru EJ22, SDS EFI, Marcotte M-300, IVO, Shorai- RV6A C-GVZX flying from CYBW since 2003- 450.6 hrs. on the Hobbs,
RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
https://www.youtube.com/channel/UCiy...g2GvQfelECCGoQ


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  #10  
Old 01-14-2017, 11:52 AM
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Mike S Mike S is offline
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Join Date: Sep 2005
Location: Dayton Airpark, NV A34
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Default

Quote:
Originally Posted by rv6ejguy View Post
EFII does not offer the fuel trim function nor some of the other SDS features.
Methinks the reference in the original post was using EFII to describe the system function, and not as a specific brand name.........

Clark, confirm or no?
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VAF 909

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Flying as of 12/4/2010

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