Question about PE

[Jonblarc7]

I have it selected to be disabled since I don?t have any cats. But couldn?t find anywhere else where I needed to disable its tables

[ShaneB]

could you post your tune

[Jonblarc7]

3-3-20 BBA_G5MAF_v15 7-22-20 final.hpt


Here you go

[Jonblarc7]

Think maybe It's because my Accelerator Pedal Position and Commanded Throttle Actual don't match. Acc Pedal is 99.6 but Commanded Throttle stays in the 60's%

I was trying to clean up my WOT VE at lunch so I made a hit.

7-24-20 1.hpl

[ShaneB]

Your alcohol PE table ramps from 1.20 to 1.247. When flex fuel is enabled those tables blend together. Also, it appears that you're just logging the wrong TPS channel, but I'm not sure on that one, just feel like I was logging the SAE one last time I had my laptop in the car. I'd try another one just to be sure.

[Jonblarc7]

So would you lean out the alcohol tables. Maybe .98??

I try the other channel tomorrow

[ShaneB]

No. That's far too lean for E85 haha. Just make it the same as your gas table, its lean enough already.

[5FDP]

I have my gas PE set to 1.175 and the alcohol set to 1.130 above 4,000-4,500rpm. It blends it nicely depending on what I have in the tank.

[Jonblarc7]

Lol
No I meant to multiple it by .98

So I?m trying to take 2% out of it

[Jonblarc7]

5FDP

It?s 1.175 PE .825 lambda and isn?t that way to rich for a NA truck. Don?t you have a newer 5.3?

[5FDP]

I run 89 octane or E85 so I blend it from 12.5 to 13.0 AFR. That's like .85 to .89 lambda.

[Jonblarc7]

That makes since

[ShaneB]

Using windows calculator, 1 / 1.175 = .851. You don't subtract the portion above 1, it's not a direct relationship like that.

[Jonblarc7]

Well I did not realize that. Thanks

[Ghostnotes]

That?s never how I would set one up....

Okay so how?

I'm targeting a certain PE ratio of 12.1 from about 3600 on up.Below that are stock numbers and figured are pretty safe. So instead of a sharp spike, I smoothed the ramp in. Unless like the stock, I should lean it out a little but im boosted and was going to leave it that way until i see what it does on the scan.

[TriPinTaZ]

Okay so how?

I'm targeting a certain PE ratio of 12.1 from about 3600 on up.Below that are stock numbers and figured are pretty safe. So instead of a sharp spike, I smoothed the ramp in. Unless like the stock, I should lean it out a little but im boosted and was going to leave it that way until i see what it does on the scan.

IMO

You might find you make a little more torque at 11.8 from 3000-5200, then 11.9 at 5600 and 12.0 till redline on a boosted application. The dyno is really where to dial this in. Basically you want slightly richer before and up to peak torque and then slightly leaner after peak torque to redline. There isn't a ton of power to be made this way vs 12.1 across the board but I'm more speaking of the slope. Some cars will want the slope leaner like 12.0-12.3, some will like 11.8-12.1. Just depends on the setup. But the basic principle still applies.

[Ghostnotes]

IMO

You might find you make a little more torque at 11.8 from 3000-5200, then 11.9 at 5600 and 12.0 till redline on a boosted application. The dyno is really where to dial this in. Basically you want slightly richer before and up to peak torque and then slightly leaner after peak torque to redline. There isn't a ton of power to be made this way vs 12.1 across the board but I'm more speaking of the slope. Some cars will want the slope leaner like 12.0-12.3, some will like 11.8-12.1. Just depends on the setup. But the basic principle still applies.

Gotcha


I had it set that way and with my setup it seems happy, no knock or black smoke. It will go to the dyno now for polishing for sure (see my post from today). I had it set to 11.8 for quite a while and i swear in 4th gear cursing it feels more responsive and smoother now. I'll give the above a shot though and lean it a little up top.It does like the slope i put in.

Thanks.

[Ben Charles]

Very low regions of RPM should never should that rich.. that will just make a car launch lazy

[Jonblarc7]

What do you consider very low regions on a NA cammed truck. I made every thing the same 1.130 at 2,560 and above. My rookie think was I?ll usually start a wot pull around that rpm?

[Ben Charles]

2 things shops that’s send me tune work all over the world often get wrong... engine doesn’t go into PE quick enough (often times in boost rigs they will be making 4-5psi and still not be in PE..

The other is below 2k rpms they have fuel wayyy to rich (stock converter sees this from a dig) this can be closer to stoich levels