Enginuity question

I am confused from looking over a couple tunes side by side and one of them makes sense but the other does not in my head. Can someone help me out and explain the difference between low detonation fuel tables and high detonation fuel tables so I can make sense of it?

don't touch the high detonation tables, thats all you need to know.

He is right.

 

If you look at the table "Primary Open Loop Fuel Map Switch" you will see that at a certain IAM the ECU will switch to that map. Default should be 0.35.

 

Assuming the IAM is above that point, which is hopefully always, the ECU will use the "Primary Open Loop Fueling" table.

Well my concern is the difference between the two tunes, I have not changed any of the values. One tune has a much leaner values in the high detonation table vs. the low detonation table.

yeah.. neat huh? lol

 

I just had a random thought, perhaps we're making it too hard for "tuned" cars to enter the high-det map.. hmmmmmmmmm...

Now what really confuses me is that when I read one of the tunes in both enginuity and ECUFlash, the tables are reversed. High detonation values in enginuity are low detonation values in ECUFlash, and vice versa???

what version rom and ecu defs xml?

The car uses the low-detonation map under normal conditions, and will switch to the high-detonation map if there has been a lot of (as you might guess...) detonation. I assume that if you fill up with 87 octane that would get you running on the high-det map, but I'm in no hurry to test that theory.

 

Like they said above, you probably don't want to change it. It's there as a safety net.

• C:\Program Files\Enginuity\ecu_defs.xml in enginuity.
  
• Version 1.29.906 for ECUFlash
  

The defs that come with Ecuflash 1.30 and earlier and extremely old (like well over a year). There was a mistake back then where the LGT primary and failsafe maps were reversed.

 

It also sounds like you are using old Enginuity definitions (although the maps are NOT reversed they are still older as the maps are no longer called low det/high det). The Enginuity ECU and logger definitions are updated independently of the software. So, you should update both. Because the Enginuity site is currently down, follow these instructions to update both the Enginuity and Ecuflash definitions (Ecuflash defs will only work with version 1.31 and later):

http://forums.nasioc.com/forums/showpost.php?p=20343079&postcount=43

Thats the ticket! thanks very much

FWIW I have my IAM X-over to high det fuel map at a much higher point then OEM.

 

I also have the IAM level for boost cut higher then OEM.

FWIW I have my IAM X-over to high det fuel map at a much higher point then OEM.

 

I also have the IAM level for boost cut higher then OEM.

With the way certain people think we should tune, 0.95 IAM? heh. I think the timing algo is not scaling with the additional cylinder pressures, it has to be accounted for somehow.

I think the timing algo is not scaling with the additional cylinder pressures, it has to be accounted for somehow.

 

I don't understand what you are getting at.

I don't understand what you are getting at.

Hypothesis: The signal to noise ratio with higher cylinder pressures should go down while the severity of any knock event goes up. Also you lose the natural scale/balance that the correction values and knock learning tables have with the stock map as you add more load and tune these maps, usually only in the high load cells.

 

Just an idea I'm kicking around.

I don't mean to jack the thread but, I hae been looking at this progam and I don't understand what "knock count" mean. Why is a 6 good but, a neg. 6 bad. Does it mean it trying to predict how close you are to knocking? What number means you have a knock? Thanks Bryan Can we get a tunner forum or sticky thread.

KC is both positive and negative, and also represent dynamic advance when the ECU is happy, at least to me knowledge.

 

+ KC is a good thing, means everything is in order and the ecu is happy with the tune and whatnot. Sharp changes in KC represents knock events, for example if you're logging and it goes 5,5,5,5,5,6,6,6,6,6,2,5,6,6. The 2 could be considered a pretty severe knock event.

 

 

Mike

KC is both positive and negative, and also represent dynamic advance when the ECU is happy, at least to me knowledge.

 

+ KC is a good thing, means everything is in order and the ecu is happy with the tune and whatnot. Sharp changes in KC represents knock events, for example if you're logging and it goes 5,5,5,5,5,6,6,6,6,6,2,5,6,6. The 2 could be considered a pretty severe knock event.

 

 

Mike

 

It is true that +KC is good, kinda.....

 

When I first started logging, I thought, "I have positive KC numbers, I guess all is well........................WRONG!"

 

If you have access to your tune, you will know how it is set up. Realistically you should always be running maximum + KC values that your tune has. This is assuming that the ECU has not been reset in a while. (if the ECU has been reset recently, depending on tune, it may take a few WOT runs for the ECU to learn its way to full power)

 

Mike is right, if you see a sharp drop in timing, you know that something is wrong.

 

Our LGT ECU is set-up to pull 2 degrees of timing at a minimum if it hears what it perceives as a knock event.

 

If you log total timing and get a knock event you will see a sudden drop in timing of either 2, 4, 6, etc degrees depending on severity.

 

 

 

Sooooooooooo, you could be pulling timing very often due to knock, and still always see + KC numbers.

First, let me say I hate Shamar. He got me looking into tunning. I come from a old street racer/ Hot Rod back round. Tunning car from the '50 and and up with carbs and points. We had to deal with things like point float and lifter gaps. We had no computers for tunning we had to use audible ques. When we had a knock. You would hear a knock. Then you would reduce the timing by 2 deg. make another run at WOT check to hear knock and repeat till you don't knock. Anyway, I what reading show a real knock. Does the KC reading show what the computer had to do to prevent a knock. I saw one map where the person had a -50 kc reading . So if Shame told me -1 is bad then the person that pull a -50 should have been able to hear the knock. I don't think many have really heard a car knock. It sounds like those old diesel Mercedes. So as long as you don't knock we are OK. The only thing besides vibration and mechanical failure is knocking. So stick with me for a minute. Why don't we tune to knock? If the computer wants to knock correct why not let it. The stock ECU job is to make he motor run it's most efficient and protect the motor. Maybe people are overturning. Are you still with me? I the 90's Edelbrock made a throttle body and a tuned port injection setup to retro-fit pre- computer . I was pretty much self contained it came it's own fuel pump, ECU and temperature sending unit. With that simple setup it was able to run with any engine setup(cam, intake,etc...) get better MPG then carbs and make more power. We also running stock ECUs on supercharged 11's mid to late 80's Mustangs. We didn't know about tunning back then and we would install cam, bigger TB's , move to 1.72 roller rockers, bigger fuel pump, and Superchargers. We know that we had to pull timing when on boost we would add a timing controller. With all that added the stock ECU was able to compensate and have the car run hi 11's low 12's and be driven everyday. That is alot more changes then we are doing on a much more advance ECU. We should be able to pool are knowledge we should be able to make the safest, most efficient tune. This worked with the DIY FMIC why not with ECUs. I don't know of any tunners that are engineer or rocket sceintist.(no offense:)) So they had to learn like the rest of us. Mod please make this a sticky. If I'm wrong on somethine please let me know.

Should I make a DIY tunning thread.

KC is both positive and negative, and also represent dynamic advance when the ECU is happy, at least to me knowledge.

 

+ KC is a good thing, means everything is in order and the ecu is happy with the tune and whatnot. Sharp changes in KC represents knock events, for example if you're logging and it goes 5,5,5,5,5,6,6,6,6,6,2,5,6,6. The 2 could be considered a pretty severe knock event.

 

 

Mike

Ok, if 2 would be severe then what about a person I read that KC was -50. He should have heard that knock. But he did not know it happened until he check his datalog. So 2 can't be that severe could it?

Ok, if 2 would be severe then what about a person I read that KC was -50. He should have heard that knock. But he did not know it happened until he check his datalog. So 2 can't be that severe could it?

 

I believe that that -50 knock count was from a different kind of ECU, maybe the 16 bit, or maybe some piggyback system.

 

You cannot even reasonably pull 50 degrees of timing, think about it. The 2 degrees of pulled timing we talk about is a literally 2 degrees, not an arbitrary knock count.

I believe that that -50 knock count was from a different kind of ECU, maybe the 16 bit, or maybe some piggyback system.

 

You cannot even reasonably pull 50 degrees of timing, think about it. The 2 degrees of pulled timing we talk about is a literally 2 degrees, not an arbitrary knock count.

So if the person is using enginuity then what else could the KC reading mean.

Knock count and knock correction are not the same thing.

 

Mitsus use a knock count. Subarus use knock correction.

 

Knock correction is in terms of degrees of timing. It can't be -50 or your car wouldn't run.

 

KC = IAM x DA + Fine Learning Knock Correction + Feedback Correction

 

FLKC and FC are always 0 or negative.

 

If you look at your dynamic advance table (also referred to as Timing Advance in enginuity), there are some areas where DA is 0. In these areas if you have any FLKC or FC then your KC will appear as negative.

 

Positive KC by itself doesn't mean much. It just means your tuner made your DA table > 0 at that location. Also, not all tuners use a flat DA table (constant value). You should rely upon IAM, FLKC, and FC to determine if there is knock.

 

Keep in mind that KC is purely for the tuner or technician. The ecu doesn't need KC. It uses IAM, FLKC, and FC. I believe that's why Subaru removed KC from the 2007 ecus.

 

merchgod wrote a complete writeup on subaru's knock control strategy on enginuity.org. Unfortunately, it's down. I've read Cobb's ST guide and it's a very similar explanation. However, there are a few additional details on enginuity.org.

Keep in mind that KC is purely for the tuner or technician. The ecu doesn't need KC. It uses IAM, FLKC, and FC. I believe that's why Subaru removed it from the 2007 ecus.

 

Linky or elaborate please!

Mickey, with regards to FLKC, do you know if there is a way to extract that table from the rom in the ecu using Enginuity? (LBGT said it can be done in ST.)