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8* of KR with cam, 3.4, FS IC, 90# springs. Nothings adding up (attached HPT logs).

Turbocharged400sbc said:
A few things of note.
From what I can tell you are using the AFR calculation that the computer uses not what a separate wideband is indicating the latter being far more useful than the former.

Also since you are now tuning... some maintenance is in order if your Upstream oxygen sensor has about 50,000 miles or more on it you need to replace it. Those sensors Q overtime and they are a trusted sensor that the PCM assumes is working perfectly even if indicated otherwise.
The AFR calculation that the computer is doing is dependent on what the tune and sensors show it and a dirty and skewed oxygen sensor is about the biggest f****** that could happen in this area.

Stay away from Bosch o2s
Click to expand...

Can you rephrase that first part?

I think its a Denso has about 10k on it at most. It switches fine if that matters.
 


The AFR number you are giving us is from the parameter ID in the PCM correct? You do not have a wideband sensor?
That pid is what the pcm is calculating....based on airflow/fuel mass.
It is what you used to compare to your wideband gauge to make sure that what the computer is commanding ie11 .4 FR is what is actually coming out of the engine. Then you know that your air and fuel calculations/tables are at least close to correct
 
Your car is running really rich, -10 ltft is not good you want it to be as close to 0 as you can get. -10 ltft means the computer is cutting 10 % of fuel

There is a guide to starting hp tuners I would recommend using to get started
 
Turbocharged400sbc said:
The AFR number you are giving us is from the parameter ID in the PCM correct? You do not have a wideband sensor?
That pid is what the pcm is calculating....based on airflow/fuel mass.
It is what you used to compare to your wideband gauge to make sure that what the computer is commanding ie11 .4 FR is what is actually coming out of the engine. Then you know that your air and fuel calculations/tables are at least close to correct
Click to expand...

Yes I am using a wideband thats where Im getting the 10.5.
 
SgtMarshal said:
Your car is running really rich, -10 ltft is not good you want it to be as close to 0 as you can get. -10 ltft means the computer is cutting 10 % of fuel

There is a guide to starting hp tuners I would recommend using to get started
Click to expand...

Regular cruising its within 0 - -5. Ill see if I can get it dialed in better at WOT
 


I'm not sure if your car is like this, but I ended up subtracting specific amounts of fuel from the Maf from 7000 hz and up to get to the target 11.5 afr. Looking at that one section I would say you need to subtract 10 of fuel
 
dont hpt have a simple log to read with out all the fancy BS? i know everyone hates on dhp and its old barbaric set up, but damn, i can read this and know what im looking at.

finish%20line%20scan%2097%20mph_zpssshf4e1x.jpg
 


I added my inj pulse width and leaned it out like you guys said looks much better. How high do these inj go? 20ms is what comes to mind but this is with my 3.4 on once I go to my 3.2 again it will probably be close. Also any comments on why my MAF is topping out at 10,500 ish doesn't matter if I have a 3.2 or a 3.4 on seems to be metering the same amount of air. I figured i was ok till 11,500

 
in the pic i posted, the "injector pw" column see its in the 16,000 range wot top of the rpm's. those are the 42's, stock that value was up to 24,000, and thats maxed out. over 20,000 or close to it is max im told reading a dhp scan. all i know is your maxing them out from personal experience.
 
you are still -9 ltft at wot, need to subtract 9% more fuel at that maf hz range. if you add the duty cycle pid to the chart you can see exactly how much headroom you have with your injectors. your o2 mv is at 938 which is getting better, I think 925 is where you want it.
 
Appreciate all the great help guys,

Where is the duty cycle located? I cant find that PID only duty cycle I am seeing is TCC duty cycle.
 


Duty cycle is a math, there is no channel for it. It appears when you log injector pulse width.

You have to add it to your charts to see it. You had it there in the first log but were not logging injector pulse width but in that last screen shot it was missing. In the default layout it's in the top with rpm and vehicle speed.
 
I think you have to be scanning "calculated airflow" as well.

I wouldn't worry about what your ltft is. As long as the pcm still has room to adjust it, which it does in your case, I wouldn't mess with it.

I would change your commanded pe. Fueling>power enrichment, and there should be a table that is commanding pe Afr vs ect. I can't for sure remember if that is the correct table. But you need to lean that out. If it's at 10.5, change it to 11.0, and see what happens.

10.5 is too rich for gas. You can cause kr from being too rich too. 11.5-11.7 is where you should shoot for.
 
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