Ecu reading from 120-140 load table in High Boost!
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Ecu reading from 120-140 load table in High Boost!
My friend and I did some data logging today to see how Al’s modified tune would turn out to be. I had significantly changed it by leaning out mid range and a much more gradual decrease of advance timing throughout the high loads and rpm’s. The lower timing map was the original one, which I set as the low octane for now, and the above one is the one I modified set as high octane.
http://www.mecah.com/timing.jpg
Well going though the data logs, the advance timing was from 19-22 degrees as average and high 20’s, low 30’s in the very high rpm’s. Lowest was 16 degrees. When I compare those numbers with my timing map, it puts me right in between the 120 to 140 load range! Is that possible? Is that why Al set the ignition numbers in the140+ load range the same?
Now, please don’t ask me how I know this, but I was getting zero knock counts most of the time. In one pull, at low rpm turbo spool up, I experienced 4 counts of knock for about 500 rpm’s where the timing was still 16+. In other small spots, I would get 1-2 knock counts for about 200 rpm’s or so. Timing would still be 19+ degrees.
A simple way to fix this is to have the timing the same from the 120- 260 load range, but I don’t want to do that. How can I get the ecu to read the 240-260 load range? what could be wrong?
http://www.mecah.com/timing.jpg
Well going though the data logs, the advance timing was from 19-22 degrees as average and high 20’s, low 30’s in the very high rpm’s. Lowest was 16 degrees. When I compare those numbers with my timing map, it puts me right in between the 120 to 140 load range! Is that possible? Is that why Al set the ignition numbers in the140+ load range the same?
Now, please don’t ask me how I know this, but I was getting zero knock counts most of the time. In one pull, at low rpm turbo spool up, I experienced 4 counts of knock for about 500 rpm’s where the timing was still 16+. In other small spots, I would get 1-2 knock counts for about 200 rpm’s or so. Timing would still be 19+ degrees.
A simple way to fix this is to have the timing the same from the 120- 260 load range, but I don’t want to do that. How can I get the ecu to read the 240-260 load range? what could be wrong?
#2
I posted a similar finding recently on a stock JDM GSR IX ECU with an AVC-R, 3" TBE and Walbro pump. There was no clear answer.
I don't feel it is right to have a whole range of load cells running the same timing, it makes no sense at all. However, it might be pragmatic when you don't know which cells it is hitting.
I don't feel it is right to have a whole range of load cells running the same timing, it makes no sense at all. However, it might be pragmatic when you don't know which cells it is hitting.
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Well,
I'm not sure about this so hopefully jack or someone will chime in and correct me if I am wrong but....
I THINK the highest load point will occur at peak torque and then fall off from there, so as you move up the rpm range (down the map) the load value will get lower (moving left on the map).
The map has to account for the highest possible load point so you end up will unused load cells at higher rpm's.
You could play with the maf scaling to get the ecu to think you are in a higher load point but what is the point. Just setup your timing map so you can easily trace the path through the load cells and adjust from there.
Once you hit peak torque you want to sustain that torque as long as you can since power ultimatley comes from torque. If the torque curve is flat in a particular region you propably do not need to ramp up timing much in that reagion and there is a point where additional timing does not net you additional power or torque.
That said, I don't think the values should just be flat filled but should (like you said) have some ramp to them. But without putting your hands on the actual car, you kinda have to go with "safe" values since every car is unique. Hence the reason Al say these are good starting points.
I'm not sure about this so hopefully jack or someone will chime in and correct me if I am wrong but....
I THINK the highest load point will occur at peak torque and then fall off from there, so as you move up the rpm range (down the map) the load value will get lower (moving left on the map).
The map has to account for the highest possible load point so you end up will unused load cells at higher rpm's.
You could play with the maf scaling to get the ecu to think you are in a higher load point but what is the point. Just setup your timing map so you can easily trace the path through the load cells and adjust from there.
Once you hit peak torque you want to sustain that torque as long as you can since power ultimatley comes from torque. If the torque curve is flat in a particular region you propably do not need to ramp up timing much in that reagion and there is a point where additional timing does not net you additional power or torque.
That said, I don't think the values should just be flat filled but should (like you said) have some ramp to them. But without putting your hands on the actual car, you kinda have to go with "safe" values since every car is unique. Hence the reason Al say these are good starting points.
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Yes, what mad said is correct.
The load numbers are roughly proportinal to mass airflow/revolution, commonly logged as g/rev. This peaks at peak toprque and falls off from there. So, at peak torque you will be at the highest load cells, but depending on you car and your mods and the VE at high RPM, your g/rev may drop significantly at higher RPMs.
This was very easy to see in DSMLink, as you could log g/rev. For a DSM, if you were over 2.1 g/rev. it would use the highest load column in the timing map, and for a highly modified car at high boost, it always stayed abouve 2.1 g/rev, even at high RPM. But, at lower boost, it could very well drop below the 2.1 mark at higher RPMs, which made the timing and fueling use the lower load columns.
Eric
The load numbers are roughly proportinal to mass airflow/revolution, commonly logged as g/rev. This peaks at peak toprque and falls off from there. So, at peak torque you will be at the highest load cells, but depending on you car and your mods and the VE at high RPM, your g/rev may drop significantly at higher RPMs.
This was very easy to see in DSMLink, as you could log g/rev. For a DSM, if you were over 2.1 g/rev. it would use the highest load column in the timing map, and for a highly modified car at high boost, it always stayed abouve 2.1 g/rev, even at high RPM. But, at lower boost, it could very well drop below the 2.1 mark at higher RPMs, which made the timing and fueling use the lower load columns.
Eric
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Originally Posted by elhalisf
My friend and I did some data logging today to see how Al’s modified tune would turn out to be.
I would be very surprised to find your car actually falling all the way to 120 - 140 KPA (~4-6 PSI) while still under WOT conditions.
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The column values aren't really a true measure of boost.. Just a rough calculation so if you consider RPM, Your Mods (hence why some aftermarket intakes are bad), weight of the car, Boost levels (And taper) you very well could end up in a much lower cell.. Other things such as the GEAR the car is loaded in, and whatnot...
Calculated load is just that, a calculated load value, it can go up or down due to a number of factors..
Calculated load is just that, a calculated load value, it can go up or down due to a number of factors..
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Originally Posted by ScrappyJack
You said you were logging knock and timing. Can you also log boost (or another load value) and TPS? That way, you can compare your RPM vs load to better give you an idea where you are on the map at any given time and rule out the extremely high timing and extremely low boost being during lift-throttle. You didn't mention what boost you are running, or the shape of your boost curve that I saw.
I would be very surprised to find your car actually falling all the way to 120 - 140 KPA (~4-6 PSI) while still under WOT conditions.
I would be very surprised to find your car actually falling all the way to 120 - 140 KPA (~4-6 PSI) while still under WOT conditions.
Originally Posted by Noogles
usually 8 degrees is the max you want to run on pump gas race gas might allow for 1-2 more degrees but isn't recomended because of the incredibly high cylinder pressure.
Originally Posted by taenaive
It must be the case of low boost. and your car is as slow as Honda civic.
Seriously, check your boost! there is no way hitting 16 in the mid with the decent amount of boost.
Seriously, check your boost! there is no way hitting 16 in the mid with the decent amount of boost.
Originally Posted by Noogles
1. What are you using to log?
2. What map is on the bottom?
post a log file so i can take a look at it.
2. What map is on the bottom?
post a log file so i can take a look at it.
www.mecah.com/log.xls
those where 5 pulls on 100% TPS.
here is one thing i realize. the max Air flow Hz is maxed at 1603.95 hz! how can i be maxing out the maf this soon??
Last edited by elhalisf; Jun 23, 2006 at 01:07 PM.
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Something does not look right with those logs... If the knock count was accurate, the timing would be getting pulled. and if the timing values were that high I would think you would be knocking a lot more...
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Originally Posted by elhalisf
all the logs that i have done where at 100% TPS. i can log boost using a 3.5 bar sensor, but i have to use the zeitronix. however, i have verified that my autometer gauge is fairly accurate.