i'm using $8d with a 305 manual with a d1sc 8lbs, 30lb/hr injectors fuel pressure is at 40 at idle, fmu is set full rich, when at wot the afr is not consistent and is too lean for my liking, it sometimes will hit 16.x 17.2, i tried adding fuel with the table PE afr vs temp and it seemed to do something but not enough, i'm using an lc1 wideband, how else can i go about adding fuel to lower the afr?

 

i've attached a tunerpro monitor image, if anyone can be of any help

 

another thing, this doesnt make sense to me, but i'm learning alot with the tuning, at 3500 rpms and up wot 4.37v tps 103.77 map target afr is 11.79, but the wb shows 15.2 at 4000rpms it shows 15.4 but the same target AFR, am i correct to assume that the ecm "knows" what it wants and is not getting it?

 

Try using AFR Tuner. Might help.
Its in the Tuning guide sticky.
https://www.thirdgen.org/forums/diy-...er-v1-0-a.html

 

It's EXTREMELY rare when anyone has any luck with one of them.

Bigger injectors, and better code, would be my answer.
8 PSI is enough that you can make some serious HP, and no being able to match the timing, and fuel to the boost will always be a headache.

Someone needs to patch the 8D for boost, IMO.

 

yeah i have used the afrtuner my afr is set to 9 in pe, still not low enough for me as i'm reading between 14-15afr, if there was a boost patch for 8D that would be awesome, is it really hard to add a 2 bar map code to it with a multiplier?

 

You may be hitting the PW limit that Z69' found.
Look at the tuning guide under "Fixing PW" in the 730 section.
Its a simple code change in any hex editor.

I've never heard what is really needed for this "boost" patch.
I'm still sucking air
Some discussion on it may prove that its not that hard to do.

 

i didnt even know there was a pw limit! what is the limit? and how do i add this patch to my axxd.bin

like the following? should there be some kind of cap so the injectors dont pulse beyond what there capable of?

 

You might check the fuel pressure and injector duty cycle as well. If the IDC is over 80-85%, you've reached their max and they are almost on all the time so you either need to up the fuel pressure or get bigger injectors. If the fuel pressure is dropping as the RPMs go up, you need a bigger fuel pump. Hope this helps.

 

my ads file is showing the wrong pulse width, but i'm using an fmu, under boost fuel pressure jumps up to 60lbs or a little over, i upped my fuel pressure from 44psi to 50psi i still have the same issue....

 

well i dont really use datamaster except for the log to run vemaster, but i was looking at a datalog, heres what i come up with

TPS% 100.0
MAP KPA 103.7
RPM 3125
INJ BPW 8.67
INJ DC 45.1

RPM 3475
INJ BPW 9.02
INJ DC 52.2

RPM 3875
INJ BPW 8.93
INJ DC 57.7

RPM 4350
INJ BPW 8.56
INJ DC 62.1

RPM 4775
INJ BPW 8.56
INJ DC 68.1

RPM 5175
INJ BPW 8.56
INJ DC 73.8

RPM 5450
INJ BPW 8.56
INJ DC 77.8

RPM 5650
INJ BPW 8.56
INJ DC 80.6

RPM 5675
INJ BPW 8.56
INJ DC 81.0

why is the pw the same in the upper rpms? is this the so called pw cap? what do you guys gather?

 

sorry, it was under the code section.
https://www.thirdgen.org/forums/diy-...limit-fix.html
see if your code has a segment that matches this.
May take some deep searching to find it and confirm it.
Look in the areas near the addresses shown, I'll bet its the same calculation.
May be the problem, might not but it can't hurt to try it.
JP

 

i found the post ok, i have this in my code

96 65 13 64 FF 03 CC FF FF DD 6B DC 6F DE F1 BD
E4 4C FE 84 1C BD E4 16 59 49 DD E2 CE 00 E2 96

but what changes am i making to it?

 

Don't forget that as you increase the operating pressure, you're also lowering the capacity of the pump. And with some pumps, capacity drops off rather quickly.

 

From what I'm seeing in the other thread you have the same values.
DE F1 BD E4 4C FE 84 1C
The bold values need to be swapped to make the fix

The final configuration you will have is:
96 65 13 64 FF 03 CC FF FF DD 6B DC 6F
FE 84 1C BD E4 4C DE F1
BD E4 16 59 49 DD E2 CE 00 E2 96
This will reverse the the positions of the two LDX's per the other thread.
Please use carefully and take precautions when first trying out anything new.

 

ah i see now, thanks a lot, i'll give it a try, so the pulse width should exceed my limit of 8.56 now?

 

All I can say is the calculation won't get limited as before.
Only testing will prove what exactly it will do. Others said they had success.
There was also a note in regards to temperature in the calculations indicating the limit was reached sooner at different temps. I'll have to re-read that post again to get that clear that in my mind.
Might want to verify the temp sensors are working good and indicating properly too.
Let us know if it helped.

 

The BPW limit is supposed to be hardcoded into S_AUJP V3:

https://www.thirdgen.org/forums/diy-...rsion-3-a.html

and is supposed to be a problem only for large cube motors. I am seeing the same thing on my 327 motor. I am not hitting the injector limit at all. I am running 24lb injectors from a LT1 and have just recently reset the constant down to 22lbs/hr. I am trying to figure out all of the variables that can be added to the ALDL defiintion so that a BPW can be reverse engineered where you can say I need this BPW at this rpm. My calc shows this, my variables are this and if the vary these items I get what I want. This is opposite of somebody saying slowly change one thing at a time and see what happens. I want to be able to predict the trend. Also I want to start doing this in OL mode to start with. This means WOT and OL idle when cold until it goes CL. What I am after is getting a AFR that follows the commanded AFR.

 

For a PE mode at WOT you have 2 tables that will give you your commanded AFR in total. PE Vs Coolant Temp and PE Vs RPM. I have been set my PE Vs Coolant Temp to 15.6% and PE Vs. RPM to 0% which gives a commanded AFR of 12.73. My WOT AFR's are in the mid 14's. The BPW for my car appears to be exactly the same as yours which does not seem to make sense but 8.56mS looks very familiar. Past datalogs have my upper PE Vs. RPM's set to 30% and above. This got me close to what I am expecting. Back to my line of thought here. From a number of datalogs I know basically what BPW I need to have at a particular RPM based on my datalog. For instance say I have a desired BPW at 3600RPM of 9.5mS. If I could calculate what is limiting my BPW to 8.56 at that RPM I can adjust the items accordingly. I can also use this logic to adjust my MAP variables which seem to be a major issue that no one has alluded to yet.

 

Here is the thread that I started in the past.

https://www.thirdgen.org/forums/diy-...-using-ve.html

trying to get what I think are the same results that you are.

 

I have been looking at the MAT threads and have a question for some of the guys out there that can really follow the code:

Has anybody looked into the Inverse MAT table being used because of the EGR? I was wondering why it is there and previous posts show that it has a profound affect on the BPW. I am thinking that I may want to disable it and adjust my MAT Comp Counts table.

https://www.thirdgen.org/forums/diy-...-question.html

 

If someone could find a combo of engine size and injector flow on a bench that yields a (for example) 10 ms pulse at 100% VE at 100 kPa, then you could just use that, and twiddle the other airflow dependent things if they become problems. Then everyone can use that as a base. The VE table doesn't necessarily have to be VE. If you do as I am indicating, you could change the XDF to show PW (at X MAT). Just find some combination that can go static by 5000 RPM at 100F MAT, and most engines will be covered.

Or did I miss something about the PW limit that is preventing large PWs no matter what combo is input?

 

i've made the changes to the bin for the pulse width, it seems that the afr went down a little bit, and gave me a new symptom, i stoped at work and the engine just dies, it did it again tonight, i opened it up a little bit, got to my parking space, and it just died, but thats not an issue, i need my afr lower and cannot figure this out, should i add fuel to the upper 100kpa tables? or should i try lowering the injector constant? although that will skew all of my ve tables.. currently i have 84.31 in the 4400 rpm +