Hp tuners help asap on quickest way to tune fuel trims

osofast1 · 11-07-2009, 11:32 AM

I am a very experienced tuner, with things like AEM EMS, Motec, ond piggy backs like the FIC, ultimate for imports.

I just bought HP tuners pro for GM and FORD, and I wanted to tune my vette since it has a vrsc1 and longtubes before I go to the track.

I really only need to tune fuel, and I have my portable tuning LM1 I am going to throw in the car for wideband purposes.. Theres alot of different tables they tune with versus say AEM or such.

what is the easiest quickest table most of you guys use?

Thanks in advance

car is an 09 z06

8850 · 11-07-2009, 11:58 AM

I have found that disabeling LTFTs works best for my 08. Get the MAF and VE table right and no learning time between tunes. You don't take a change of leaning out with positive LTFT at WOT. And improved idle as well. There are posts on HP Tuners forum that you can refer.

TurboLX · 11-07-2009, 02:15 PM

In a nutshell:

1) force open loop operation; disable STFT and LTFT, set min temp for Closed Loop to Max
2) force MAF only operation by setting the RPM threshold to zero
3) take steady state wideband error measurements at as many MAF breakpoints as possible to retune the MAF Hz vs airflow table
4) return to blended MAF/VE mode (rpm threshold) and Closed Loop operation
5) enjoy.

If you're efficient, this takes all of about 30 minutes on a good load bearing dyno.

osofast1 · 11-07-2009, 06:42 PM

GREAT! My HP tuners cannot open my VCM file in my ZO6???

I asked specifically if I could use this on an 09(since I heard some of the ECU's were locked) but they insisted it would NOW work on my car perfectly

I can open any other map I download, but not mine.

I connect and it downloads the file from the cars obdII port, and then asks to save file name before I view it, when I try to open the file it says:

Definition failed to load. You will be unable to edit this file.
Please email this file to support@hptuners.com with a VCM suite info log

WTF?! I wanted to tune for the track tommorrow, and at least turn the fans on eairler and a few other things.

any help.

Randy@RaginRacin · 11-08-2009, 11:50 PM

You need the beta version

DSteck · 11-10-2009, 04:37 PM

Quote:

Originally Posted by 8850

I have found that disabeling LTFTs works best for my 08. Get the MAF and VE table right and no learning time between tunes. You don't take a change of leaning out with positive LTFT at WOT. And improved idle as well. There are posts on HP Tuners forum that you can refer.

A positive fuel trim before going into power enrichment will not make it lean out. If anything, it will richen up the fueling. Running in open loop all the time is not neccessary.

8850 · 11-10-2009, 10:52 PM

Quote:

Originally Posted by DSteck

A positive fuel trim before going into power enrichment will not make it lean out. If anything, it will richen up the fueling. Running in open loop all the time is not neccessary.

I've heard the opposite from some. I don't claim to be a tuner so I don't really know whilch is correct. But disabeling LTFTs for me seems to work good. Driving 100 miles, so some say is necessary for the ECM to learn, every time I change a tune isn't going to work for me.

DSteck · 11-11-2009, 10:55 AM

Quote:

Originally Posted by 8850

I've heard the opposite from some. I don't claim to be a tuner so I don't really know whilch is correct. But disabeling LTFTs for me seems to work good. Driving 100 miles, so some say is necessary for the ECM to learn, every time I change a tune isn't going to work for me.

When the tune is done correctly, it doesn't have to learn anything.

It's always going to tweak fuel trims in closed loop, but when the calibration is accurate, the fuel trims will be very low since you're already delivering the right amount of fuel to begin with.