Tune help on swapped Rx7

[fastfalcon94]

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.

[5FDP]

You don't have to change the dynamic airflow, you can but it's not needed. You just have to set the MAF fail high to 0hz and all 3 MAF dtc's to first error. They can not be set to No error reported or no MIL light.

[schpenxel]

Post tune.

[fastfalcon94]

Post tune.

Here it is:

http://www.802projects.com/images/random/tune.zip

[5FDP]

MAF dtc's must be set to first error if you removed the MAF, you can not set them to no MIL Light. Not having them set right can screw with how it runs.

[fastfalcon94]

MAF dtc's must be set to first error if you removed the MAF, you can not set them to no MIL Light. Not having them set right can screw with how it runs.

This guy says the "SES Enable" needs to be set for them but to set them to "No MIL Light"....


http://files.hptuners.com/support/SDTuningGuide.doc

"9. Set MAF Fail High Frequency to 0 & MAF Fail Low Frequency to 0
The PCM will detect a MAF fault as soon as you key on and thus revert to speed density mode.
The PCM requires a MAF DTC to be set to revert into speed density mode. If you set all of your MAF DTCs (101, 102, 103) to no error reported the PCM will not revert to speed density.
The factory settings will work but if you are concerned about an SES light, set the DTC's to No MIL Light. The PCM will still set the code for a MAF fault and thus still revert to speed density.
"

[5FDP]

There are lots of different write ups out there. First error is the correct way to do it.

[fastfalcon94]

There are lots of different write ups out there. First error is the correct way to do it.

It definitely won't hurt for me to try "First Error". What do people do about the Check Engine Light?

Also any recommendations on PE Delay and Enrichment Ramp in?

[5FDP]

Most just disable the SES light, some leave it on at first to know that the DTC is set and in SD.

PE delay can be up to your preference. I prefer to have a much lower rpm delay of like 1,500-2,000 and make the MAP kpa enable higher. An example is like having the MAP kpa at 70kpa, rpm delay at 1,500 and then the pedal enable at 65%. That way pretty only my foot is going to determine when I enter PE because beyond half throttle I should already be above 1,500 rpm and 70kpa in the intake and once my foot reaches past 65% it will enter enrichment.

Enrichment ramp is rate set between 1-2 is fine.

[schpenxel]

I leave it on at first then disable the light later.

If you log MAF airflow, VE airflow and dynamic airflow you can usually see which it's actually using. Dynamic is the final airflow it's actually using which comes from either MAF, VE or both

[fastfalcon94]

So I made some changes and went for a drive. I stomped on it through 2nd and 3rd gear about 5 times and it never hesitated like it did before. I've still got some more driving to do. Good idea on the airflow logging.

What I changed:

- set the dynamic airflow so that it won't try to switch over to a maf until 7k rpms. This shouldn't affect anything
- set the PE delay settings from 1.00000 and 5000rpms to 1.5 and 2000 rpms
- for traction control I had it disable ETC correction and timing correction. Previously I had it only disabling fuel cut. So now all traction control should be off.

I may turn some stuff back on one at a time and see if I can figure out exactly which change made the difference. For now though I'm going to get my fuel table dialed in so I can turn back on the fuel trims and all the speed density multipliers I disabled.