Injector scaling and latecy for different injectors.
#91
Evolved Member
iTrader: (2)
Join Date: Oct 2002
Location: Somewhere
Posts: 1,328
Likes: 0
Received 0 Likes
on
0 Posts
From the maps, you probably have either the scaling wrong or the latency wrong ..
I'd rather say if its not broke .. don't fix it !!
once you change, you will probably need to redo the entire fuel map ..
I'd rather say if its not broke .. don't fix it !!
once you change, you will probably need to redo the entire fuel map ..
Last edited by gunzo; Mar 17, 2007 at 08:42 PM.
#92
Evolved Member
iTrader: (18)
Any one out there have FIC 850cc dialed in??? My fuel trims were both at -2 and over the days they have shifted just a tad...like 3 & -6....i used the latency values off the AEM spreadsheet but dont know where to set the scaling values...i find that my car turns on with the latency values but i had to lower the scaling all the way to 550 to get the car to even idle right....what a pain...
Last edited by alan678; Mar 19, 2007 at 05:57 PM.
#94
Evolved Member
iTrader: (2)
Join Date: Oct 2002
Location: Somewhere
Posts: 1,328
Likes: 0
Received 0 Likes
on
0 Posts
Right now it just seems your global scaling is too low thats why you have to set 9.x on the fuelmap to see actual AFR of 11.0
#97
Evolved Member
iTrader: (18)
On average, your crusing injector pulsewidths will be double your idle injector pulsewidths. So, any changes that you make in the injector deadtime will affect idle twice as much as it will affect cruising. But, yes, it will affect both if they are both in the same V range that you are adjusting for.
DSMLink used a global fuel setting slider and then an injector deadtime value to tune the injectors. Their global slider was basically the injector scaling value in the ECU and their deadtime was basically what we get to adjust in the voltage latency tables.
But, with the years of experience with DSMLink and seeing others dial in injectors, the above holds true.
Basically, what we did with DSMLink is as follows:
1. Choose a global setting (ECUFlash injector scaling number)
2. Log trims at idle and cruise
3. If trims are roughly the same, but positive, then you need to increase your global fueling, or in terms of ECUFlash, you need to lower your injector scaling number.
4. If both trims are roughly the same, but negative, then you need to descrease your global fueling, or in terms of ECUFlash, you need to raise your injector scaling number.
5. If idle trim is more positive than cruise trim, then you need to increase the dead time, or in terms of ECUFlash, you need to increase the latency value.
6. If the idle trim is less positive than the cruise trim, you need to decrease the deadtime, or in terms of ECUFlash, you need to decrease the latency value.
Note: After #5 or #6, you may need to readjust #1 accordingly.
Note 2: #5 and #6 implicitly answer ludikraut's questions about affecting idle and cruise trims. Basically, let's say that the IPW is 1ms at idle and 2ms at cruise. If you adjust the deadtime to add 100us (.1 ms), then you are affecting the idle fueling 10% and the cruise fueling 5%.
Eric
DSMLink used a global fuel setting slider and then an injector deadtime value to tune the injectors. Their global slider was basically the injector scaling value in the ECU and their deadtime was basically what we get to adjust in the voltage latency tables.
But, with the years of experience with DSMLink and seeing others dial in injectors, the above holds true.
Basically, what we did with DSMLink is as follows:
1. Choose a global setting (ECUFlash injector scaling number)
2. Log trims at idle and cruise
3. If trims are roughly the same, but positive, then you need to increase your global fueling, or in terms of ECUFlash, you need to lower your injector scaling number.
4. If both trims are roughly the same, but negative, then you need to descrease your global fueling, or in terms of ECUFlash, you need to raise your injector scaling number.
5. If idle trim is more positive than cruise trim, then you need to increase the dead time, or in terms of ECUFlash, you need to increase the latency value.
6. If the idle trim is less positive than the cruise trim, you need to decrease the deadtime, or in terms of ECUFlash, you need to decrease the latency value.
Note: After #5 or #6, you may need to readjust #1 accordingly.
Note 2: #5 and #6 implicitly answer ludikraut's questions about affecting idle and cruise trims. Basically, let's say that the IPW is 1ms at idle and 2ms at cruise. If you adjust the deadtime to add 100us (.1 ms), then you are affecting the idle fueling 10% and the cruise fueling 5%.
Eric
Lets say #5...idle trim (3) is more positive than cruise trim (-6), an increase of the latency value is recommend.....how do you go about changing the scaling?? Does it follow the latency and go up to the next settings or does it get lowered?
#98
Evolved Member
iTrader: (2)
Let me give a quick example using your numbers and show you how you would have to change the resulting scaling:
Idle trim: +3%
Cruise trim: -6%
Assuming that your idle pulsewidths are half of your cruising pulsewidths and idle is about 1ms (just using round numbers for the example...you would have to log to find out for sure), then let's see what adding 100us (.1 ms in ECUFlash) would do to the trims:
The 100us would add 10% fuel to idle, so it would subtract 10% from the idle trim, now making it -7%.
The 100us would add 5% fuel to cruise, so it would subtract 5% from the trims, now making it -11%.
So, now you have:
idle: -7%
cruise: -11%
So, now if you scaled your injectors to be 7% larger, then your trims would be:
idle: 0%
cruise: -4%
Of course, if you make any changes to your injector scaling, you will have to make sure that you make the necessary changes to your open-loop fuel maps, since the injector scaling change will change your AFR.
Eric
#99
Evolved Member
iTrader: (18)
Let me give a quick example using your numbers and show you how you would have to change the resulting scaling:
Idle trim: +3%
Cruise trim: -6%
Assuming that your idle pulsewidths are half of your cruising pulsewidths and idle is about 1ms (just using round numbers for the example...you would have to log to find out for sure), then let's see what adding 100us (.1 ms in ECUFlash) would do to the trims:
The 100us would add 10% fuel to idle, so it would subtract 10% from the idle trim, now making it -7%.
The 100us would add 5% fuel to cruise, so it would subtract 5% from the trims, now making it -11%.
So, now you have:
idle: -7%
cruise: -11%
So, now if you scaled your injectors to be 7% larger, then your trims would be:
idle: 0%
cruise: -4%
Of course, if you make any changes to your injector scaling, you will have to make sure that you make the necessary changes to your open-loop fuel maps, since the injector scaling change will change your AFR.
Eric
Idle trim: +3%
Cruise trim: -6%
Assuming that your idle pulsewidths are half of your cruising pulsewidths and idle is about 1ms (just using round numbers for the example...you would have to log to find out for sure), then let's see what adding 100us (.1 ms in ECUFlash) would do to the trims:
The 100us would add 10% fuel to idle, so it would subtract 10% from the idle trim, now making it -7%.
The 100us would add 5% fuel to cruise, so it would subtract 5% from the trims, now making it -11%.
So, now you have:
idle: -7%
cruise: -11%
So, now if you scaled your injectors to be 7% larger, then your trims would be:
idle: 0%
cruise: -4%
Of course, if you make any changes to your injector scaling, you will have to make sure that you make the necessary changes to your open-loop fuel maps, since the injector scaling change will change your AFR.
Eric
I will try this tomorrow!!! Thanks!!!
#100
Evolved Member
iTrader: (6)
Join Date: Jul 2005
Location: Charleston, SC
Posts: 1,228
Likes: 0
Received 0 Likes
on
0 Posts
OK, so in addition to a post I made in the MAF scaling, here is another that is injector related:
I recently purchased a Perrin Fuel rail, fuel pressure regulator and PTE 680 injectors off a friend and slapped the set-up in my car. Now, here is a few details.
His car was set-up by a Jester flash, but for cams and a few other things. I looked at the Jester flash, and copied ONLY his injector scaling value (609) and his voltage latency tables to be able to have it at least running better than not touching it (Latency table). I hope this doesn't cause any problems, but here is the latency table that was from the flash:
4.69 3.528
7.03 1.869
9.38 1.416
11.72 0.960
14.06 0.648
16.41 0.480
18.68 0.360
Now, I know I have to tune this specifically to my car, and that is what I am going to attempt to do now...
But, in looking at the table posted, it looks as though the numbers are way off, especially the 11.7v. Should I reset my values to what is posted on the chart, then re-log what is going on?
Now, in my most recent logs, my O2 sensor feedback trims data:
Low: 5
High: 164
Average: 102
Fuel Trim Low:
Low High and Avg: 100
Fuel Trim Med:
Low:109
High: 115
Avg: 114
Fuel Trim High:
Low High & Avg: 139
I would assume that with the averages of the Med and High fuel trims being over 100, that I should try to recenter the values? (Or do I need to be hit with a bat because I don't know wtf I am doing? I have most of the other stuff figured out, but this is getting me because I am doing it for the first time.) I need to be ed-u-mic-kated more.
I recently purchased a Perrin Fuel rail, fuel pressure regulator and PTE 680 injectors off a friend and slapped the set-up in my car. Now, here is a few details.
His car was set-up by a Jester flash, but for cams and a few other things. I looked at the Jester flash, and copied ONLY his injector scaling value (609) and his voltage latency tables to be able to have it at least running better than not touching it (Latency table). I hope this doesn't cause any problems, but here is the latency table that was from the flash:
4.69 3.528
7.03 1.869
9.38 1.416
11.72 0.960
14.06 0.648
16.41 0.480
18.68 0.360
Now, I know I have to tune this specifically to my car, and that is what I am going to attempt to do now...
But, in looking at the table posted, it looks as though the numbers are way off, especially the 11.7v. Should I reset my values to what is posted on the chart, then re-log what is going on?
Now, in my most recent logs, my O2 sensor feedback trims data:
Low: 5
High: 164
Average: 102
Fuel Trim Low:
Low High and Avg: 100
Fuel Trim Med:
Low:109
High: 115
Avg: 114
Fuel Trim High:
Low High & Avg: 139
I would assume that with the averages of the Med and High fuel trims being over 100, that I should try to recenter the values? (Or do I need to be hit with a bat because I don't know wtf I am doing? I have most of the other stuff figured out, but this is getting me because I am doing it for the first time.) I need to be ed-u-mic-kated more.
#101
Evolved Member
iTrader: (6)
Join Date: Jul 2005
Location: Charleston, SC
Posts: 1,228
Likes: 0
Received 0 Likes
on
0 Posts
OK, so in addition to a post I made in the MAF scaling, here is another that is injector related:
I recently purchased a Perrin Fuel rail, fuel pressure regulator and PTE 680 injectors off a friend and slapped the set-up in my car. Now, here is a few details.
His car was set-up by a Jester flash, but for cams and a few other things. I looked at the Jester flash, and copied ONLY his injector scaling value (609) and his voltage latency tables to be able to have it at least running better than not touching it (Latency table). I hope this doesn't cause any problems, but here is the latency table that was from the flash:
4.69 3.528
7.03 1.869
9.38 1.416
11.72 0.960
14.06 0.648
16.41 0.480
18.68 0.360
Now, I know I have to tune this specifically to my car, and that is what I am going to attempt to do now...
But, in looking at the table posted, it looks as though the numbers are way off, especially the 11.7v. Should I reset my values to what is posted on the chart, then re-log what is going on?
Now, in my most recent logs, my O2 sensor feedback trims data:
Low: 5
High: 164
Average: 102
Fuel Trim Low:
Low High and Avg: 100
Fuel Trim Med:
Low:109
High: 115
Avg: 114
Fuel Trim High:
Low High & Avg: 139
I would assume that with the averages of the Med and High fuel trims being over 100, that I should try to recenter the values? (Or do I need to be hit with a bat because I don't know wtf I am doing? I have most of the other stuff figured out, but this is getting me because I am doing it for the first time.) I need to be ed-u-mic-kated more.
I recently purchased a Perrin Fuel rail, fuel pressure regulator and PTE 680 injectors off a friend and slapped the set-up in my car. Now, here is a few details.
His car was set-up by a Jester flash, but for cams and a few other things. I looked at the Jester flash, and copied ONLY his injector scaling value (609) and his voltage latency tables to be able to have it at least running better than not touching it (Latency table). I hope this doesn't cause any problems, but here is the latency table that was from the flash:
4.69 3.528
7.03 1.869
9.38 1.416
11.72 0.960
14.06 0.648
16.41 0.480
18.68 0.360
Now, I know I have to tune this specifically to my car, and that is what I am going to attempt to do now...
But, in looking at the table posted, it looks as though the numbers are way off, especially the 11.7v. Should I reset my values to what is posted on the chart, then re-log what is going on?
Now, in my most recent logs, my O2 sensor feedback trims data:
Low: 5
High: 164
Average: 102
Fuel Trim Low:
Low High and Avg: 100
Fuel Trim Med:
Low:109
High: 115
Avg: 114
Fuel Trim High:
Low High & Avg: 139
I would assume that with the averages of the Med and High fuel trims being over 100, that I should try to recenter the values? (Or do I need to be hit with a bat because I don't know wtf I am doing? I have most of the other stuff figured out, but this is getting me because I am doing it for the first time.) I need to be ed-u-mic-kated more.
If I quote myself, does that mean I am talking to myself?
I figured it out, the latency maps posted actually made the fuel trims (Med and High) come close to 100, If memory serves me correctly the Med went from Avg: 114 to 102 and the High Avg from 139 to 110. So, it definately looks like they helped, and now it's a matter of fine tuning them.
#103
EvoM Guru
iTrader: (5)
I can give you the settings I'm using, the problem is their just a guideline, but the settings I used gave me map AFR's real similar to actual AFR's
Keep in mind I'm running a blowthrough MAF so there may be some adjustment necessary for the latency at higher RPM.
Injector scale: 665
Battery Voltage: (some of the values are stock at low voltages, kinda figure the car is in bad shape at 4 and 7 volts.. )
4.69: 3.312
7.03: 1.680
9.38: 1.392
11.72: 1.104
14.06: 0.960
16.41: 0.696
18.69: 0.504
This was from trial and error, you should get decent results with this.
Keep in mind I'm running a blowthrough MAF so there may be some adjustment necessary for the latency at higher RPM.
Injector scale: 665
Battery Voltage: (some of the values are stock at low voltages, kinda figure the car is in bad shape at 4 and 7 volts.. )
4.69: 3.312
7.03: 1.680
9.38: 1.392
11.72: 1.104
14.06: 0.960
16.41: 0.696
18.69: 0.504
This was from trial and error, you should get decent results with this.