I have a 94 Rx7 that I swapped an LS2 motor in out of an 06 pontiac gto. It's a stock motor. I couldn't run a maf though as my intake setup is very short (about 14 inches) and has a good bend. People have used a maf here but run into their own set of problems. My goal is to eliminate the maf basically and have it drive more or less like stock. I use speed density on my 3000gt with aem and love it. So I did a bunch of research, and followed the speed density tuning steps online. This is where I set the maf fail frequency to 0, disable the CEL for certain diagnostic codes, and bought the breakout harness and have an IAT sensor wired into my intake etc...
I set all the fuel multiplier tables to 1 and disabled LTFT's, so that the only real thing controlling fuel should be my primary VE table. I built my own AFR Error chart/histogram and set it to a minimum of 50 cell counts. I did a bunch of driving around and table multiplication and smoothing. I think my afr is pretty decent. I need to manually smooth it up some, but the car runs perfect cruising around and doing steady pulls. What I've noticed though is that if I punch the throttle at times it just loses power instantly. Not all the time but probably 50% of the time. In my logs it shows as leaning out. I thought maybe it had something to do with Torque Management or Traction Control. Traction Control has fuel cut disabled though...
Any advice would be appreciated. Here you can see where I've punched it in 2nd gear. My ecu is commanding a 12.8 AFR and my wideband is leaned right out. My fuel table doesn't do anything crazy in this area of the cells... The delivered Engine Torque shows 391 ft pounds but I couldn't find anything in Torque Management that would eliminate fuel. Shortly after I punch it and let off after it hits a wall, I punch it again and you can see that this time it does the pull...
http://www.802projects.com/images/random/logfile.zip
*Also as a side note it would do this before I even starting adjusting anything. I read the ls2 used speed density up until about 3600 rpms and then started using the maf. So originally I thought that is all it was. Since I was running SD the car was probably falling on it's face when it got to where the maf would take over. But even after doing some steady WOT pulls and adjusting that area of the fuel table; it still does it. The fuel table in this area wasn't awful either. I assume GM had it adjusted fairly decent in the event that someone's maf sensor would fail. I do have the "High RPM Disable" still set to 3600 rpms. This is where the maf would take over. I didn't change this, but didn't read anything online that said I would need to either. I'm assuming it's not applicable if there is no maf.
I do have a large silicone elbow too going from the Throttle body to the K&N intake. It's about 10" long. I wonder if it could be collapsing. But that would restrict air and I'd think the tune would go really rich and not lean. I know a few other people run the same coupler too so I don't think that is the problem.