Playing around with the 2.7 software (ECU and TCU)

[JoeTe]

Here EOI table that i calculated with a EOI builder program

STOCK


My EOI with SOI mod that I running actually

[RTB]

Hi JoeTe,

Thanks for sharing your tables. Do you know the SOI address you used?

I wonder what I have done so wrong? I get a max SOI of 17.1 deg, with a max EOI of 20 deg at the same point. Your calcs show a max stock EOI of 29.1 deg. I only picked one of the duration maps. I will run the calcs with all the duration maps and if I end up with an EOI similar to what you have found. That could be where the difference is.

Might need to go back to the beginning and see if I can find an error in my thinking.

We must have a different understanding of N75. I can't see that playing with the N75 will lower boost. I can see how it will lower boost response, but the ECU will still try and target what is in the boost maps. My understanding of the N75 is that it is a base map. An initial point for the VNT to go to, then the ECU will tweak from their to hit boost. Increase the N75 and you end up with a lively turbo that will hit boost quickly, but may overshoot. Lower N75 and you and up with a laggy turbo that takes its time to hit boost point. That said, I haven't played with the N75 as most comments i've seen say just leave it alone unless a different turbo gets fitted.

I currently run lower boost at low load to hit an AFR of 20 - 22, and a higher boost under load to keep exhaust temps down. This was achieved by the boost map.

[RTB]

At this point, I have 1 SOI map, 1 Fuel Rail Pressure Map, and 6 Duration Maps. As far as I can tell, this is the base information to calculate the EOI.

Just run the calcs on all 6 duration's with injection quantities of up to 80mg/stroke or 94mm3 as used for the duration and rail pressure maps. This is 5mg/stroke more than stock maps call for.

None of my calcs have and EOI as far as the 29.1 from the EOI builder program. Max I see is 24 deg ATDC. Guessing at this point that the map labelled Duration 1 is the normal running map when the engine is up to temperature.

JoeTe, do you know the addresses of the SOI, rail pressure, and duration map you used for your changes? Maybe I am missing them?

Not sure if these maps are in the correct order. All maps show a retarded injection cycle at low RPM and a more advance injection cycle at higher fuel and RPM. This would seem reasonable. They also loose some of that advance with max fuel and max RPM which like mentioned will be due to the fuel rail pressure limiting. If the max rail pressure was bumped up, this would bring the mid-point of injection back to a more advanced center point. I'm not going there...

Maps created using linear fuel flow increase, ignoring DW maps which are non-linear.

Edit:- Just found an error in my mid-point calc, but it doesn't really change much.

Duration 0


Duration 1


Duration 2


Duration 3


Duration 4


Duration 5

[JoeTe]

Originally Posted by RTB

Hi JoeTe,

Thanks for sharing your tables. Do you know the SOI address you used?

I wonder what I have done so wrong? I get a max SOI of 17.1 deg, with a max EOI of 20 deg at the same point. Your calcs show a max stock EOI of 29.1 deg. I only picked one of the duration maps. I will run the calcs with all the duration maps and if I end up with an EOI similar to what you have found. That could be where the difference is.

Might need to go back to the beginning and see if I can find an error in my thinking.

We must have a different understanding of N75. I can't see that playing with the N75 will lower boost. I can see how it will lower boost response, but the ECU will still try and target what is in the boost maps. My understanding of the N75 is that it is a base map. An initial point for the VNT to go to, then the ECU will tweak from their to hit boost. Increase the N75 and you end up with a lively turbo that will hit boost quickly, but may overshoot. Lower N75 and you and up with a laggy turbo that takes its time to hit boost point. That said, I haven't played with the N75 as most comments i've seen say just leave it alone unless a different turbo gets fitted.

I currently run lower boost at low load to hit an AFR of 20 - 22, and a higher boost under load to keep exhaust temps down. This was achieved by the boost map.

Hello SOI address is $72AA0 - offset 0,023437

Really dont know if my calculates are good or yours because I did with EOI Builder program

Anyways my EOI its until 100 IQ and you always show only until 80 IQ

My SOI map show 16,71 degrees at 4000 rpm and 2200 bar
Duration for 80mm3 @ 1300bar (we can stay around 1300-1350 bar at 4000 rpm) its around 1388 uS in degrees -> 4000*360/60*1388/1000000= 33,3 degrees
Duration for 100mm3 @ 1300bar its around 1823 uS in degrees -> 4000*360/60*1823/1000000= 43,7 degrees

EOI @ 4000 rpm - 80mm3 = 33,3 -16,71 = 16,29 degrees
EOI @ 4000 rpm - 100mm3 = 43,7 - 16,71 = 27 degrees

We cant know exactly because our SOI map its MAP based instead IQ and we dont know exactly what pressure are working but more or less we can know around what it is
I think maybe your problem its uS to degrees conversion?

About n75 and boost like I said i never played but if work like you said (i think you are in right way) you can mod boost map and n75 in that area although maybe they only play with n75 to get just a little bit less of boost anyway I really dont sure that fuel consuptiom will be better without boost even my mind say that really will be reverse way more boost will be lean afr and can increase a little bit the efficiency of engine maybe the way of reduce consuption its because you in that area will be less power and like you dont have power you will be more patient when you need acelerate but really you are not increasing efficiency.
This theory I seen people because SDI engine (NA) have better consuptiom than TDI

[RTB]

Hi JoeTe,

I did look at the EOI builder program, but I read that not everyone was happy with it, so just decided to do it in Excel. I am the type of person that really needs to be able to see the insides of the processes I use too, so at least in Excel I know for sure what is happening every step of the way.

We are using the same SOI map, but I stopped using the 0,023437 offset and just went to a time based conversion to crank angle after JeanLuke questioned the results. Also found the comment from earlier where AdrianD mentioned that our maps are in the time domain. Turns out that it might actually not be a big difference anyway.

As for the IQ shown on my tables. Yep, they are displayed in mg/stroke, that's why they only go to 80. This is 5mg/stroke higher than the stock tune calls for. In the SOI and Rail Pressure calcs, this is converted to mm3, so ends up at 94 mm3. 85mg/stroke is needed to get the full 100mm3. The 450 tune I did went all the way there.

But, you prompted me to find the difference. It was in the RPM. I only really look at the zones I will be operating in. I just pushed the calculator uo to full fuel and full RPM. That is where the 29.1 EOI was hiding.

Glad it worked out, I was having some serious doubts about my Excel skills for a while there. Just one more of the many Rookie mistakes I have made on this journey.

[JoeTe]

Originally Posted by RTB

Hi JoeTe,

I did look at the EOI builder program, but I read that not everyone was happy with it, so just decided to do it in Excel. I am the type of person that really needs to be able to see the insides of the processes I use too, so at least in Excel I know for sure what is happening every step of the way.

We are using the same SOI map, but I stopped using the 0,023437 offset and just went to a time based conversion to crank angle after JeanLuke questioned the results. Also found the comment from earlier where AdrianD mentioned that our maps are in the time domain. Turns out that it might actually not be a big difference anyway.

As for the IQ shown on my tables. Yep, they are displayed in mg/stroke, that's why they only go to 80. This is 5mg/stroke higher than the stock tune calls for. In the SOI and Rail Pressure calcs, this is converted to mm3, so ends up at 94 mm3. 85mg/stroke is needed to get the full 100mm3. The 450 tune I did went all the way there.

But, you prompted me to find the difference. It was in the RPM. I only really look at the zones I will be operating in. I just pushed the calculator uo to full fuel and full RPM. That is where the 29.1 EOI was hiding.

Glad it worked out, I was having some serious doubts about my Excel skills for a while there. Just one more of the many Rookie mistakes I have made on this journey.

Good to know we are now at same point

What are you looking for playing with SOI?

This EOI is from C30 amg if you want take a look to compare (again was do it with EOI builder so maybe its not "perfect")

[RTB]

Mainly just looking to learn really. That said, the more I learn, the more I can see some potential to optimise.

What I really wish I could look into more is the actual program that runs it all. Not so much on the ECU, but for the TCU. I have a mate that loves his Fords. He is able to modify the full structure of the running code for his TCU. I am yet to find anything that allows that for the EGS52 fitted to our cars.

Strange below with the C30 EOI that it advances and retards as the revs go up. I need to look more into diesel tuning. The internet just does what it is best known for, contradicts itself with every new page read.

As I play, I have started putting together SOI and rail pressure mods to fit to my philosophy of what the SOI - EOI should look like. This again is just for learning right now. I mean it isn't new stuff. Sure, every engine is different, but someone out there must know the basics for what is best as a general rule.

I have seen comments like advancing the timing will increase power, but reduce economy. But if I increase power at any given point, I will then need to reduce fuel to maintain the original power, thus improving my economy???

The opposite comment I have read that by retarding timing the power goes down, but economy improves. Well if I am on the fwy, and I retard the timing which then reduces power, I will slow down. This means more throttle, more fuel for the same load????

What does make sense is that if the SOI goes further into the compression stroke, then this takes away power due to increasing cylinder pressures while the piston is still trying to compress the gases (reverse torque). But at the same time, if the EOI goes further down the power stroke, then we take away peak combustion pressures and the power goes down. So ideally we would start and stop injection at TDC, or a tiny bit before as RPM increase (to allow for the combustion time delay). Doing this though would see extreme combustion temperatures and pressures and burn holes in pistons and wipe out bearings. Not to mention requiring rail pressures extremely high and Nox emissions through the roof. No smoke though!!

Since a crank angle of less that TDC +- 10 deg really has minimal effect on torque, it would seem reasonable that at light load/RPM the SOI should be just before TDC, and the EOI could go anywhere up to around 10 deg ATDC. From that point the SOI would need to advance at a rate slightly faster that the EOI moves back as injection duration increases. This would create the average injection timing advance as IQ and RPM increases to allow that little bit more time for combustion to complete.

A knock sensor, or at very least a knock prediction calculator would obviously be very helpful for engine health.

Am I way off the mark with this??