Usually when you exceed the range of a table, the pcm will continue on with what ever the last value was. Since the fuel table is rpm based, you should be able to continue adjusting the A/F with changes in that table. Is it a perfect way to tune? No. But it should work.

 

Right, that's what I said before... just making sure we agree that upping the MAF failure limit won't fix the lean problem.

 

Until I have the car in front of me where I can make a change, then try it, then make another chance, then try it again, I don't know. I upped the limit and disabled the P0103 code. I'm helping someone in another town about 100 miles away that got a mail order tune from another shop with his STS kit. If the changes I made to his PCM make it driveable at all at WOT, he's going to bring me the car to dyno tune it. Right now, he just sent me his PCM and I sent it back.

 

He's maxing out the MAF with his STS kit? Is it the basic 5psi kit on a stockish engine?
I've got an STS kit on mine, but haven't had much of a chance to tune due to weather... and the fact that I'd been running it w/o MAF in SD mode. Hopefully I'll clean the oil out of the intake and be able to run a MAF system soon though.

 

MAF high freq threshhold maximum @ 65K+. The MAF cal high point is @ 512 grams/ sec. 512 g/sec flow is much less the 65K. It appears the this is a high limit set in the PCM code. Stock high freq setting was 10,700, and, it sure did set a PCM with that value. I run an ATI D1 with a 7 5/8 -> 3.4 pulley setup, and, have not found a PCM error with this maximum setting and reving to 6.8K.

I do know that I prefer the use of the MAF in closed loop mode to control AFR @ low speeds. Better drivability and throttle response.

I have not investigated disable of the MAF high freq error trigger. Also, if this error check is disabled, will the PCM auto default to speed density mode? I cannot comment.

Accel, FAST, Bigstuff3 are very tempting.

 

It's a 383 heads/cam car with an upgraded turbo STS kit. Don't remember which one he said it was though. No intercooler though. He said it is making 7~8 psi boost.

I know on the LS1 PCMS, we keep all the MAF codes enabled and set the fail freq to 0 to force them into speed density to tune VE tables or to just run a speed density tune. I also like keeping the MAF for the reasons you said. I probably should have set the fail freq higher than 15000. I should know something in the next couple of days if what I did helped any.

 

Update. The changes I made did not help. I'll be getting the car to play around with in a couple of days.