Originally Posted by alan678

My fuel map prior to the injectors were .3-.4 off on the settings...what are you talking about specifically???

Originally Posted by l2r99gst

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

Originally Posted by alan678

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?

Originally Posted by l2r99gst

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

Originally Posted by tkklemann

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.