Why should PE Table be flatlined?

[Corvette_Guy]

Hi,

saw in a youtube video the PE table should be flatlined and you know if its a good tune or not.
Also saw it in a few uploaded tunes from the databank.

For me as a beginner its logical to correct the error between commanded afr and my WB and then
change the PE to tables to what i want.
But the video stated it as last resort and its not the way you typical do it.


Thanks

[QTR FMS]

most of the time flat line afr will give you best result but not necessarily, some richen pe where the engine knock like peak torque area and then make it lean up top,

keep it flat if you have no reason to make a curve,

yes try to dial in your afr error to less than 2% with flat pe first

[07GTS]

it can be because the factory sometimes rape the PE to keep fueling emission safe, and as mentioned its easier to dial in fueling to a flat PE then a changing one, because of the slight delay from injectors to wideband u will always have an AFR error if the commanded is changing from stoich to PE and different PE values if they are different throughout the rpm range so u will have to weed that out error data when adjusting fueling to read correct which u dont have to do with a flat PE to follow, once u have it correct with a flat PE then if it likes a little more or less at any rpm it can be adjusted from there in the PE table but keep changes smooth from cell to cell if u do change them

[TCSS07]

Much easier to control fueling on 1 solid afr then a fluctuating afr to get fueling inline and then like others said you can adjust it from there.

[Corvette_Guy]

Great info, thanks!

Didnt thought its such an easy logical answer.

[Ben Charles]

Doing it flatline is the wrong way and lazy, never seen ANay engine want the same fuel across the entire RPM band while in PE..

Low load Fueling, peak Tq, upper rpm fueling ALL want different fueling... period

[cobaltssoverbooster]

^+1 to Ben Charles
I do afr runs with a flat line and monitor peak torque hp numbers on the dyno. Once I've been through the range I populate the table with the commanded pe values that net the peak dyno output values through the rpm range. Minor clean up and tweaking after that and I'm usually close to where it wants to be.

I've never finished a tune with a flat line.