hellcat injectors on 6.4 scat need help -33% fuel trims at idle

i put hellcat injectors on my 6.4 scat and i can get the numbers close enough to start up but it is still running ruch and consistently -33% on the stft at idle and and there is a huge hesitation when the throttle is stepped on before anything happens since the injectors were put on. I know its the injectors because the car and tune were perfectly fine before the injectors were put on. Please can somebody help me scale in these injectors so i dont run the engine too long trying bad tunes and blow up the scat thanks.

Attachment 155097
Attachment 155098

bfd cam
walbro 525 fuel pump
catless straightpipe
hellcat injectors

What is the part number of the injectors? The earlier Hellcat's used a different injector than the 2021+ ones do.

Attachment 155100

If it was running perfectly before, what made you change them out?

What data did you input into the fuel injectors cells?

i had them lying around somebody gave me for free and i want to do e85 and long tubes soon but also want to make the hellcat injectors work with the 93 tune first for my own research and learning

and im running ones from the 2020 and older model set

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Originally Posted by WOTuning

What data did you input into the fuel injectors cells?

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the tune is uploaded here

Try this Attachment 155104

I changed the injector pulse width vs fuel mass tables (and a few others) to match that of a Hellcat car.

I turned NN back on since you're still running a stock cam/engine other than injectors and changed the VE tables back to stock as well.

Your part throttle timing table needs work too

Quote:

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Originally Posted by WOTuning

Try this Attachment 155104

I changed the injector pulse width vs fuel mass tables (and a few others) to match that of a Hellcat car.

I turned NN back on since you're still running a stock cam/engine other than injectors and changed the VE tables back to stock as well.

Your part throttle timing table needs work too

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it has a tsp BFD cam which is why nn is off still dialing it in but it was comfortable driving how the tune was, the spark tables are pop and bangs/flame tune, it shoots flames out the back on decel while driving with those spark tables, not for everybody but i like it and people know its me when they see the car

ill try the tune tomorrow when i get back to the shop, i had my own i have been working on, got me closer but definitely not there yet from my end

Quote:

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Originally Posted by WOTuning

Try this Attachment 155104

I changed the injector pulse width vs fuel mass tables (and a few others) to match that of a Hellcat car.

I turned NN back on since you're still running a stock cam/engine other than injectors and changed the VE tables back to stock as well.

Your part throttle timing table needs work too

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I uploaded this and when I step on the pedal it acts like I have vtec or something and bounces up and down on the revs ridiculously

This is almost there, it starts and runs and drives again but there is a massive delay on the pedal now, and still -20 to -30 fuel trims. any ideas would help trying to get these hellcat injectors to work on the cammed scat has been hell.

Attachment 155119
Attachment 155120

Did you reset adaptives?

Still don't know what part number injectors you are using ...

Quote:

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Originally Posted by Stoopalini

Did you reset adaptives?

Still don't know what part number injectors you are using ...

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68170238ab 2020 and older model injectors and yes every time i take a new log an upload the file the fuel trims are reset and i let id idle then drive it. i got this data to work pretty well, car seems happy and gained a bit of power where it was maxed out on fue before and has a bigger initial kick on it.

Attachment 155122

You should manually reset adaptives in the scanner's "Special Functions" after making these sorts of changes. I can't tell from your reply if that's what you're doing or not though, and the beginning of your log shows a large negative LTFT.

Your trims still do not look very good though. It appears to be running lean when under a high load in closed loop with STFT's going over 30% at times. Then when it enters PE mode, the positive fuel trims are sometimes carrying over too .... but without a wideband, you don't know what the AFR/FAR is doing. I would guess it's leaning out, but who knows.

How do you know it was maxed out on fuel before?

Is this your personal car, or a customer's car?

Quote:

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Originally Posted by Stoopalini

You should manually reset adaptives in the scanner's "Special Functions" after making these sorts of changes. I can't tell from your reply if that's what you're doing or not though, and the beginning of your log shows a large negative LTFT.

Your trims still do not look very good though. It appears to be running lean when under a high load in closed loop with STFT's going over 30% at times. Then when it enters PE mode, the positive fuel trims are sometimes carrying over too .... but without a wideband, you don't know what the AFR/FAR is doing. I would guess it's leaning out, but who knows.

How do you know it was maxed out on fuel before?

Is this your personal car, or a customer's car?

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my car i swapped and built it myself

Attachment 155131

the log wont upload but im in -7 to 7% now for fuel trims with this dataset, under high load still leaning out

this thread went from a plea for help to a stream of consciousness, here is the tune that works

Attachment 155132

this is how i set up my chart to scale in the injectors, copy the data from the log paste special half % and then reset adaptives and relog

Attachment 155146

lol

Quote:

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Originally Posted by LilSick

lol

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i was struggling until i received enlightenment from the data, im coming to you when i have free time for that datalogging lesson, i really need it but dont have the time or spare cash at the moment

That is my fault, i totally omitted the BFD cam and other parts. I Simply thought you were just installing HC injectors in a stock 6.4.

Attachment 155148 Try this one, my apologies. NN is off, VE is for a little larger cam in a 6.4 but should be close in fueling. Injector data is still HC based.

Quote:

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Originally Posted by WOTuning

That is my fault, i totally omitted the BFD cam and other parts. I Simply thought you were just installing HC injectors in a stock 6.4.

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you are good i appreciate the help because i still learned something form your tune file and used the data you used to scale it, its not not directly in the final tune but in the math for getting it close it was very helpful. Car is within +-3% error now on ve and fuel trims ive done 10 logs and resets since and driving like a dream ill upload a final file when im done today working on it and have a final revision, but this is the current dataset that rips me out of my seat and drives like a dream.

Attachment 155149

im going to try this tune and see if the drive-ability differs with the different dataset, im curious to see how hellcat based data work vs the scat based data i have been using.