PE tuning

[jaronow]

Thought i would throw this out there for the I5 guys... over the weekend i looked at the PE enrichment table and discovered something very odd... from 2000-3000 RPM it was commanding a 12.8 A/F ration and it would dip down to almost 12 flat at 3000 or 3200 and then climb back up to almost 12.5 until alomst 5000 rpm where it will go back down to command almost a 11.3 A/F ratio... i straighented this table out...

i didn;t drop the commanded a/f by much, but by smoothing out the rpm table from 2400 and up, which is where my PE kicks in, the truck is much faster when you get on it.... i changed my A/F to command a 12.5 or so A/F at 2400 and it gets down to aound 11 flat at 5400 to 6200 which is my shift point and it made a notice able difference, i would reccomend taking a look at this table and if you have a Wideband O2 maybe you can get your A/F lower, i know these I5's are supposed to command a 10.5:1 compression ratio, so we should be able to go lower, i just don;t want to without knowing what my A/F is

[Bill@HPTuners]

part of it is COT enrichment remember

[jaronow]

yup.... i can tell that i probably can;t go much leaner without some detonation or probelms, the motor is telling me this with how it feels when i hit PE mode.... but the change i made is really nice... the truck goes threw first gear insanely fast now, i can go all the way up to 45 and shift into 2nd before finishing a typical left hand turn, and that is with my intake temps around 100 degress out here in the desert sun!!!!!

[jaronow]

Hey foff... i just looked at teh COT tables and they don;t even engage until over 1700 degrees farenheight so i don;t think that is having any factor on our trucks... unless we are missing tables as there are only 3. the adder max, adder min and temp thresholds,

[NorthernYankee]

I must be missing something...but where is this table located?

[Bill@HPTuners]

which table?

[NorthernYankee]

Thought i would throw this out there for the I5 guys... over the weekend i looked at the PE enrichment table and discovered something very odd... from 2000-3000 RPM it was commanding a 12.8 A/F ration and it would dip down to almost 12 flat at 3000 or 3200 and then climb back up to almost 12.5 until alomst 5000 rpm where it will go back down to command almost a 11.3 A/F ratio... i straighented this table out...

The one he's referring to in this post.

[Bill@HPTuners]

under engine-fuel control-power enrich

[NorthernYankee]

So we are talking about the "EQ Ratio vs RPM" table.

Thanks Bill I just wanted to make sure I was lookin at the same thing.

[Bill@HPTuners]

yup yup

[NorthernYankee]

I know this is a bit OT but I have a quick question you know how when you mouse over a button it gives you a lil description of what the button does. Well sometimes the description is very long and doesn't fit in the box and you can't resize the window to read it. So I usually go to the help file and read it there. But for this table the description is not in the help file.

Is there any way else that I can get to the info.

[Bill@HPTuners]

can you post your file? I didnt bring my flash drive today...I'll take a look.

[NorthernYankee]

Here ya go bud.

[Bill@HPTuners]

its in there:
"V8 Power Enrich Fuel Multiplier vs. RPM: This is the main table that is used to tune WOT fuel for post 1999 V8 engines. The values in this table are Fuel/Air multipliers (or AFR divisors) ie. values greater than 1 are richer, values less than one are leaner. The values relate directly to the Stoich AFR and the resulting commanded AFR is Stoich divided by this PE multiplier. Eg. if the multiplier is 1.1 then the commanded AFR will be 14.7/1.1 or 13.36. "

[NorthernYankee]

Oh ok, I just saw v8 and kinda ignored it...I will need to look harder next time...lol

Thanks again man

[Bill@HPTuners]

like chris said in the other thread ls2's are nearly identical as far as parameters as I5 tuning other then the VE tables.

[zq8bob]

Your initial table sounds about right... remember, you wanna be a little fat around peak torque, lean as you approach max HP, and then fatten up like crazy to redline. I think the gain your seeing, is just that you leaning some of the stuff thats commanding stupidly fat ratio's like 11.5 and up... I'm kinda expecting the truck to really like the 12.3 to 12.6 range of AFR... Finally got my wideband all wired up, just hafta get the bung welded in and I should be playin with this.

Foff... I'm a little fuzzy on COT. Basically, it's extra fuel that gets added to cool combustion temps when the cat is overheating, correct?

[jaronow]

remeber that these things make peak torque around 2200 rpms, but yes you are right... since i changed the tables to more of a 12.6-12.3 range it loves it... i can feel a large change in how 1st and 2nd accelerate

[zq8bob]

Is it that low? It's been so long since I looked at a dino for one, that I had forgotten it was that low. I was thinking like 2800 or something... Why did you choose to not let the truck hit PE until 2400, after peak torque?

[jaronow]

because my i drive the truck around at about 2000-2200 RPMS to keep the alternator load high enough to power my 1200 watt amp for my W7 and my 400 watt amp for my componet speakers, if i let the RPMS drop below that i have light dimmage and other things going on with the system, so i didn;t think it would make a difference since when go WOT or even close to my PE enable TPS the RPMS are already at 2400 or so