Hi,
New to tuning and just got my HP Tuners. Is the wideband O2 necessary to do just a basic tweek on the car?? I'm running an 04Z with a set of AR LT's high flow cats and a Haltech CAI.
Thanks,
Leo
I just did a little ten minute run around to gather some data and see how the program works. It looked like the timing and all was pretty good. No Spark Retard, the LTFT looks strange between the two banks, about 5% difference. The STFT stays pretty close side to side.
I think it is more reading time and finding a local dyno with HP Tuners.
I too just got hptuners and have similar mods on my z as well. I've talked with a local tuner that is well respected and he does it w/o a wideband. He's using the voltage readings from the o2 sensors that's recorded in the log files I believe. He's compared his work w and w/o a wideband and is within .1 from widebands reading. I'm going to try mine without and go from there.
Okay so I guess it is off to find a shop who has HP Tuners and get a tune.
Thanks
You don't need to go find a shop. You are the shop now.
You don't have to have a wideband. I started out without one and I probably spent more money on gas than the wideband would have cost in the first place. Without a wideband, it takes much longer. With a wideband you can tune each parameter in just 3-4 runs and it will be d*mn near perfect.
This is the wideband I bought. http://www.plxdevices.com/products_SMAFR.htm $195 It doubles as my narrowband, so you don't have to weld a new bung in, just replace on of the front narrowbands that are already in there. Once you get your wideband, follow the directions below:
For VE Tuning with a wideband,
You need to:
- set the Engine/Fuel Control/OL & CL/Closed Loop Closed Loop Enable/ECT vs IAT to 284* across the board. This will put you in open loop along with setting the MAF fail freq to 0.
- on the same page as above, you want to disable LTFT
- also on this same page, in Open Loop/EQ Ratio, set all to 1.00 or I just change the ones from 140* and up to 1.00 (this will command 14.63 or stoich)
This step can be done several ways too. You can leave it as is if you want or change it to 1.13 which will command 13.0 AFR, it doesn't really matter what you are commanding, because the % error will still be the same. After going back to Closed Loop you won’t use this table anymore.
- in Engine/Fuel Control/Fuel Cutoff set DFCO enable temp to 284*
- in Engine/Fuel Control/COT, Lean Cruise set COT to disable
- in Eng. Diag/Airflow set MAF fail freq to 0 (you should also unplug the MAF if you can. If you are driving a 2001 and newer C-5 , the IAT is wired in the same plug, so you can’t unplug the MAF without doing some rewiring. They are seperate in the earlier C-5s)
- Now go log. Make sure you log VE for AFR, commanded AFR, and AFR percent error. I log first and then change the cell hits required to 25 for the percent error.
- Right click/Copy the percent error histogram
- Open Editor and use the paste special/multiply by % to the Engine/Airflow/General Airflow/Main VE/Primary table.
- Then, if you have a 1997-2000 C-5, copy the even numbered MAP lines to the secondary VE table by using the copy/paste method. Save and "write calibration only" to the PCM. Drive and see where you are.
Wash, Rinse, Repeat until your VE tables are in line. It should only take 3-4 runs.
After this, reset the MAF fail back to 14000 (leave everything else as is for now) and do the same thing for the MAF tables using MAF vs Output Freq (Hz) histograms instead of the VE histograms.
I too just got hptuners and have similar mods on my z as well. I've talked with a local tuner that is well respected and he does it w/o a wideband. He's using the voltage readings from the o2 sensors that's recorded in the log files I believe. He's compared his work w and w/o a wideband and is within .1 from widebands reading. I'm going to try mine without and go from there.
Yea right, the guy that did my first tune was well respected too. After I got HP Tuners and looked at his tune, I had to start over from scratch. My car would hit the dreaded code 1514 (reduced power mode) at 6000 rpm. This cuts fuel to several cylinders and you can floor the gas and you get no response. I thought the motor had blown, the first time it happened. On top of this, my Injector Flow Rate was 113% at 5800 rpm, which isn't realistic because they can't flow more than 100%. Now my Injector Flow Rate is 75% at 6500 rpm and making noticeably more power. My fuel trims were not touched and the WOT was just a guess, a very rich guess. I also had 29* of timing, and running very rich at idle, because he had copied part of another guys tune who had a bigger cam in his car and required that amount of timing.
You can tune that way somewhat, but narrowbands are only accurate from ~14.0-15.0 AFR or ~.450-.550 mv. If the AFR is above or below this it is just a guess. He would have one heck of a time tuning the MAF if there was any mods to the air intake system. And WOT would be impossible to tune without a wideband because the AFR would need to be set around 13.0 AFR and the narrowbands can't read that AFR. The wideband is accurate from ~ 8.0 - 22.0 AFR.
The narrowband is very good at what it is intended to do, which is to keep your car running at stoich (14.7 AFR). If the AFR is above or below that, all it knows is that it is above or below, they don't know and don't care what the AFR is, just that it needs to tell the PCM to add or subtract fuel to get it back to 14.7. Make sense?
Tuning without a wideband can take weeks to do right. You have to change your LTFTs and then drive the car for ~ 100 miles for the car to learn the changes. Do that over and over until it is spot on. With a wideband you can do it in a day if you wanted, no less than a weekend.
Sorry if it sounds like I am ranting, but I just went throught this. I was getting so frustrated with tuning that it was getting to where it was a chore to drive my car and took the fun out of it. I tuned it with the wideband in a weekend and now I just have to tune for the fun of it.
I too just got hptuners and have similar mods on my z as well. I've talked with a local tuner that is well respected and he does it w/o a wideband. He's using the voltage readings from the o2 sensors that's recorded in the log files I believe. He's compared his work w and w/o a wideband and is within .1 from widebands reading. I'm going to try mine without and go from there.
Run away from this guy - fast and far. If he's well respected, and doesn't use a wideband, those who respect him must be a bunch of illiterate mouth breathers. Narrow band sensors are only accurate .5 afr either side of 14.7, and only then within a narrow temperature range. You have a relatively expensive performance car, spend an hour and Google the words narrowband, wideband, and afr. Post back if you can find anyone that advocates tuning via narrowband sensors.
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Best regards,
Bill
Calgary, Alberta, Canada
2003 Quicksilver roadster , 1SB, F55, QF5, MN6, Z06 Ti catback, 2 cat H-pipe & air lid, Euro red/amber tails, Vette Net, and HP Tuners s/w - available for free to anyone in Calgary
The only way I personally would trust a tune without a wide band is if the tune was created on a car that was on a wideband and that car was identical to mine and then flashed to my car. Even then, I would want a wideband to confirm the tune.
...and the 2 new sets of racing wheels...and the 2 new sets of racing tires...and the new seat restraint system...and the new HP tuner thing...and the new headers...and the new shifter...and the new wife
Just kidding...I'm just jealous...Good luck on the MBA test tonight and racing this weekend...Love 'ya...Dad
Corvette Store
Is wideband O2 a must?
The only way I personally would trust a tune without a wide band is if the tune was created on a car that was on a wideband and that car was identical to mine and then flashed to my car. Even then, I would want a wideband to confirm the tune.
