Timing and fuel trim

[farmtruc]

Quik +1 on what Pavetim said, you want your ltrims slightly negative during cruising and anything not in PE mode, so that when your foot goes wot, ltrims go to zero, then you can nail down the a/f ratio and make commanded = actual.
If they are positive, you can't do that.
Having the ltrims positive just to richen up wot is more work and you won't always have what you're commanding in the end.

Pavetim, I completely understand what you're saying, the only statement that I... Is that you have to scale your MAF table to get ltrims negative and positive as well during non PE cruising. The VE table is mostly used in open loop and cold startup, then you scale the maf after the engine warms up.

There's a little more to it, but maf is used to scale ltrims during operating temps, ve is used for open and cold startup.

[Pavetim]

Oh yeah I do the MAF at the same time as the VE table too, forgot to mention that. You want the MAF freq correction factor as close to 1.0 as possible too. Sorry thought we were just talkin about trims. But yeah for people keeping the MAF you can tune your VE table using LTFT, PE using WB, and MAF all at the same time if you've got the right calculations.

[Frenchy]

But yeah for people keeping the MAF you can tune your VE table using LTFT, PE using WB, and MAF all at the same time if you've got the right calculations.

Details? First I've heard of that, but I'm still new to this.