AFR and Tune Questions

[Cazbah362]

OK, So I have been building my tune lately and working through being a newbie. Car is a 99 Camaro manual, 6.0 LS3 heds, BTR Stage 3, 92mm TB, LS3 MAF 4" tube, headers, 4.10's and I live at 5500 altitude and this will be a street car with some spirited driving as often as practical.

I just went through and tuned the MAF cutting off narrows, tempatures and a few other items and now have turned it back on. I feel I ma now at the point where I should start putting more fuel in and adjusting the timing a little bit. I don't want to jump in and start doing this without some guidance from persons with more experience. With that said, attached is my LOG, what would you recommend my next steps to be based off the LOG? Do I fatten the VE tables up, then run it around the block and re-adjust as necessary? Timing, when should I start on that?

Thanks -

[Lakegoat]

You need to log cylinder airmass, dynamic air, spark retard. Looks like fueling is pretty close in the no load areas. Without seeing the tune, we can't tell whats going on with your higher rpm fueling---it is rich. Running 11 according to the wideband and should be around 12.5. MAF curve probably needs to be adjusted. Look at PE settings also.

[5FDP]

Don't blindly fatten anything up. Use your wideband sensor as a tool, that is how you should tune it.

Get the MAF dialed in with the wideband and then do the VE table with the wideband.

It's got like no timing in it under heavy load, that is killing power but like he said above you need to log more data to see what is going on. Fueling is rich all over and timing is being pulled way back in power enrichment.

[Cazbah362]

Lakegoat and 5FDP, thank you, now a couple of more stupid questions:

1. Fuel is rich according to which part of the the log? LTFT? because the WB shows to be right at 14.7 low 15s?
2. Getting the MAF to a 0 is a PITA, is this normal or is this altitude, cam and me being new? I did bring it from 25+ (I assume this is where a tuner would spend a majority of their time?)
3. How do you log or what is the best method to log:
a. cylinder airmass
b. dynamic air
c. spark retard (I thought this was in the current LOG?)
4. any pointers in the attached tune?


Attached is my tune, I will work on the MAF more to focus towards the 0 before moving to VE and timing

Thanks in advance

[5FDP]

The fuel trims show that it's rich. The wideband shows that it's around 14.7 because the fuel trims are doing their job to bring the fueling there. I think you understand that.

Getting the MAF or VE to zero is impossible, it's always going to be slightly off. If I can get the MAF or VE within 3% of zero using my wideband in open loop with no fuel trims, I would call that good enough. The fuel trims once back in closed loop can do the rest of the work for me, if they are bouncing around 3-6% it's good enough.


The log is missing the data for a, b and c because you didn't log them. Cylinder airmass and knock retard and not listed in the main channels list on the left.

On a quick run through of the tune. The power enrichment EQ ratio is rich for a NA engine. It's fine for now as you fix the fueling but it should be leaned out to around 12.2-12.5 AFR commanded once things are dialed in.

Burst knock is set wrong. 0.000 means is always active, you want it at 8.000 to disabled it.

You have the torque management max torque vs rpm table set to zero, you want it maxed out to disable it.



More logs with those changes and the more data in them will be a better help to see what is going on.

[Cazbah362]

5DFP, thanks -
Now understand on a, b and c - I will add tonight

Question: Would it be best to disable Burst Knock, my understanding is this is generally only capture on initial tip in / WOT? My approach was yes, this is a NA engine, and turning it off is not bad - Your thoughts?

Will make changes, drive and work on targeting 12.2 to 12.5

[Cazbah362]

Made changes today and added knock, cyl mass and spark retard. Attached is the updated log and tune.

Please some recommendations.

I adjust the Power Enrich a bit and timing to help drive ability, definite improvement