Need help with MAF and timing.

[ho52806]

I've been working on my tune now and am pretty happy with the way the car runs so far. I have a LS2 6.0L with 232/236 .595/.595, CAI, ported TB and heads, 3000 stall, exhaust and 3.73 gears.




I have tuned on a dyno with a wideband but only made basic changes to PE and adjusted the high/low timing tables to not produce knock and where they made most HP and TQ. So far car runs great! Could have better mid range I think.

In hindsight, I should have nailed the VE, MAF, and base timing and base airflow before the dyno - but I got a super deal.

Now, I that have updated and fine tuned idle airflow and my VE table and have 2 questions.

1) How do I tune the MAF high and low? Can I do this via recorded histo data? (my wideband is several hours away)


2) On the dyno I adjust hot/cold timing without touching the base timing which was totally stock. How do I check WOT timing using the scanner tool? and how do I choose to modify the base timing tables? I have been trying different #'s based on highest produced vacuum on MAP sensor at idle.


I believe once I've nailed this down, I would have an overall better driving car. Right now, it's fast at WOT only!

[5_Liter_Eater]

Yep, the changes you did on the dyno to get the AFR dialed in should have been done to the MAF table. Ideally you'd set the PE table to the AFR you want to be at and alter the MAF or VE (in SD) tables to make it jive.

You can use these histograms but I wouldn't use recorded data. You'll need to set your PE, do some logging and copy and paste % the AFR errors into the low and high MAF tables.
I'm not sure if the plot filter follows the HST file but make sure you have the filters of [PID.2301]>5700 in the high MAF histogram and [PID.2301]<5700 in the low MAF histogram.

I'm not sure what you mean by hot and cold timing but you should just be able to log ignition timing advance to see your total timing. The default histogram does that just fine.

[Monster'06]

Yep, the changes you did on the dyno to get the AFR dialed in should have been done to the MAF table. Ideally you'd set the PE table to the AFR you want to be at and alter the MAF or VE (in SD) tables to make it jive.

You can use these histograms but I wouldn't use recorded data. You'll need to set your PE, do some logging and copy and paste % the AFR errors into the low and high MAF tables.
I'm not sure if the plot filter follows the HST file but make sure you have the filters of [PID.2301]>5700 in the high MAF histogram and [PID.2301]<5700 in the low MAF histogram.

I'm not sure what you mean by hot and cold timing but you should just be able to log ignition timing advance to see your total timing. The default histogram does that just fine.

I'm sure there's more than one way... Can't you use [Sens.80] (MAF Flow Freq) to filter, too? I looked at [PID.2301], and it just said MAF FLow. Does it also return frequency?

[ho52806]

I lost you monster. What is sens.80 and where do you find it.

[5_Liter_Eater]

I believe they are the same. They both report the MAF frequency.

[Monster'06]

I lost you monster. What is sens.80 and where do you find it.

It's in the sensor column, and it reports MAF Flow Frequency.

[Monster'06]

I believe they are the same. They both report the MAF frequency.

Cool...