General WOT fueling question on 2013 Challenger

[Pector55]

2013 Dodge Challenger R/T 5.7l Auto 5sp
Mods: CAI, 180* Tstat, JBA ceramic coated long tube headers into catless mids, into a 3" Heartthrob exhaust.
LC-2 wideband but not tied into my HP Tuners yet so I'm using Logworks. The wideband was calibrated and it does appear to record properly at part throttle.
I am running 93 octane with as much as 10% ethanol

I've been slowly tuning my car and I have the fuel trims adjusted to where they are pretty good. The ltfts are <3 and stfts are <5 in the majority of the fields. I have finally started doing WOT runs to adjust timing and fueling and I have a question.

Stoich is stock at .0688 and I've not changed this.

Question 1: I believe a fair target AFR on these hemi engines is 12.0 - 12.5: Is that a fair statement? I have read where others have gone even more rich.

Question 2: How quickly should I expect to see the car adjust the AFR?
Looking at the Logworks, I expect to see the AFR jump up during the shifts but it seems like it isn't moving to the 12's very quickly.

Question 3: I noticed that my TPS% maxes out at 86.x% while WOT. Is that normal?

Here are a couple of pics. One is of the Logworks. I was sitting at an intersection where I waited a bit to make sure there was no traffic before doing the run. I pulled onto the road and didn't just mash the pedal because I didn't want to spin the tires.

Also, I copied the FA Power Enrich into Excel, then added it to Stoich and used another table to show the inverse (AFR being commanded) for reference.

2016-01-14_1101.png2016-01-14_1102.png

[Mep_q8]

Stoich is stock at .0688 and I've not changed this.

I normally change this to a 0.068 just so I can do the math easier in my head when commanding PE.

Question 1: I believe a fair target AFR on these hemi engines is 12.0 - 12.5: Is that a fair statement? I have read where others have gone even more rich.

That's a good AFR target

Question 2: How quickly should I expect to see the car adjust the AFR?
Looking at the Logworks, I expect to see the AFR jump up during the shifts but it seems like it isn't moving to the 12's very quickly.

Increase your PE Enrichment rate

Question 3: I noticed that my TPS% maxes out at 86.x% while WOT. Is that normal?

Yes this is normal.

[Pector55]

Thanks.. I considered modifying how quickly PE ramps but I wanted to see if anyone else was doing it that way as well.

[14ramsport]

Thanks.. I considered modifying how quickly PE ramps but I wanted to see if anyone else was doing it that way as well.

how much did you increase the PE ramp i dont want to increase it to much

[RonSSnova]

It would benefit you to add the WB to your scanner. HPT has made it very simple for us.

[Pector55]

how much did you increase the PE ramp i dont want to increase it to much

I bumped mine up to .0025 and it did really ramp it up quickly.


What I am finding is that I still have an issue with my TPS. My TPS voltage does not seem to register very quickly and as a result, I am at WOT with the car still in closed loop.

Looking at the 1st Row (red) and the 2nd Row (purple) you can see when I floored it. But when you look at the 3rd Row (Green) you can see that TPS just sort of comes along and slowly rises. It's not until the vertical line that the car recognizes that it needs to be in open loop. As a result, that entire first gear AFR was up in the 14's. Is it a bad TPS or is this really typical?


EDIT: I found a couple other threads where people have changed the WOT Pedal Threshold from 3.510V down to either 3.3 V or 3.0 V. I may do that along with a throttle recalibration procedure to see if she gets into open loop more quickly.

[Pector55]

It would benefit you to add the WB to your scanner. HPT has made it very simple for us.

Not really. I have to box it up and send it in and pay a lot for it. I'll get to that eventually.
Edit: Don't take that as though I'm being a smarta55.. I'm just saying that I'm aware and it's in the works.

[Pector55]

Quick follow up:

I performed the throttle calibration procedure and left my WOT Pedal Threshold at 3.5v. I noticed on 2 WOT runs that my TPS quickly went straight to 86% as expected this time. I wanted to post the update in case someone else experiences a similar issue.

[Plum7o2]

Quick follow up:

I performed the throttle calibration procedure and left my WOT Pedal Threshold at 3.5v. I noticed on 2 WOT runs that my TPS quickly went straight to 86% as expected this time. I wanted to post the update in case someone else experiences a similar issue.

Thank you for the update. Most post never have an ending I will try this tonight as I am having the same issue with my pedal voltage and tps not reading exact.