....and my HO and LO are the sameOriginally Posted by EC_Tune
How come my VE never stabilizes ....... always seems to be off 1-2% in easy ranges. Sometimes more in the higher RPM/MAF areas. If its 10 degrees cooler ambient, does it make sense that my VE error will be more negative??
....cooler air = denser = richer ???????
I am adjusting by %-1/2 and smoothing the last two times.
Here is todays........I want to start MAF..... what do you think???
DH
well..GM has a terrible Airmass Calclulation.......and my HO and LO are the same
How come my VE never stabilizes ....... always seems to be off 1-2% in easy ranges. Sometimes more in the higher RPM/MAF areas. If its 10 degrees cooler ambient, does it make sense that my VE error will be more negative??
....cooler air = denser = richer ???????
I am adjusting by %-1/2 and smoothing the last two times.
Here is todays........I want to start MAF..... what do you think???
DH
you would think its would be cooler = richer...but its not cause GM was stupid and didnt do any real world testing..they just plugged in ideal gas laws....and flunked the class...
to get your day to day...temperature to temperature....fueling correct
you will need to mess with the complex cylinder chage bias in your Airflow tab..I suggest starting with a value in the middle or the two extremes...in your case this # = 1.0(even blend of IAT/ECT in the calculations
then you will have to retune your VE table as it will change it by probably 7~10% higher in some places..
and then double check your day to day...and adjust acordingly
this has been my method on many many vehicles and it works well as a starting point...you still have to tweak it for your car...but its a start
-Scott -
Scott
First of all, thanks for giving me MORE to think about
I checked my table and it is gradiated between .8 and .09 !!!!!!
I don't think I am ready to mess with thisBut when I am ..... you are saying that you monitor the VE after making adjustments?? Mine is biased way towards the IAT currently.....correct??
Anyways....I did my last VE log on the way home. Going to enable the MAF and start loging it tomarrow.
....nothing stopping me from returning to the VE at a later date, right
DH
Last edited by Dirty Howie; 03-20-2007 at 12:18 AM.
This looks pretty darn good to me Howie. If I filter out cells with hits less than 3 hits you're within +/- 4%. I say call it good and start tuning the MAF.
Bill Winters
Former owner/builder/tuner of the FarmVette
Out of the LSx tuning game
Thanks Bill ..... hope your rightThis looks pretty darn good to me Howie. If I filter out cells with hits less than 3 hits you're within +/- 4%. I say call it good and start tuning the MAF.
Anyways I will post a log of maf I did today. It wasn't very good as it started to rain and got slipery. Plus I don't know if REAL humid/rain air affects the maf???
DH
Is it normal for there to be no MAF readings below 3000HZ ?????
Here is a log from today....not sure if I should use it. Wanted to do some easy logs up to 7000-7500. Then do WOT.......
DH
With a 402? Yes...
Air hog... LOL
You're the one Al Gore was warning us about...
Always Support Our Troops!
Howie,
Have you set up your MAF AFR Error histogram?
Your upper Hz look good but your lower Hz need some tweaking. Not bad for a first SWAG. I think you'll find MAF tuning to be much easier then VE tuning.
Bill Winters
Former owner/builder/tuner of the FarmVette
Out of the LSx tuning game
Remember, he has an 04. No Hi MAF & Lo MAF just 1 MAF table. LOL
Always Support Our Troops!
You hear that Howie? If it wasn't for you, Al Gore wouldn't have anything to bitch about!!With a 402? Yes...
You're the one Al Gore was warning us about...
Guy's I just want to thank you for all your questions and postings in here. I'm just starting the process of tuning my VE's and this thread has help tremendously I'm getting close so I'll be keeping my eye on the MAF tuning as I'm heading in that direction soon.
2000 NBM Camaro Z28
Mods:
SLP Lid & K&N, AHR Headers + 3" catted Y and Mangaflow, !EGR, !AIR, BMR CM STB, ST Front 35mm and Hellwig Adj. Rear 22mm Swaybar, Adj. Rod/Rod PHB, Koni SA's, Ground Control Springs & Adj. Ride height, and HPTuners.
Al Gore needs a MAF on his mouth and WB on his ass.........With a 402? Yes...
You're the one Al Gore was warning us about...
DH
Here are a couple more logs
Check out MAF3 which I took this morning. I had audible ping and KR. I did a calibration using that log. Then did MAF4 log on the way home. No ping or KR and the ambient temps were indentical.
I want to do 2nd gear WOT to redline as recommended by Russ. But trying to find a place to do this on the way to work is proving difficult. I may just pull off on side of freeway and wait for a break in traffic.....
DH
Looking good!
Bill Winters
Former owner/builder/tuner of the FarmVette
Out of the LSx tuning game
That's what I do. I wait on the side of the entrance ramp until I see a break in traffic, then slowly get into third. I ease along in third at about 1200 rpm until the break goes by, then I MASH it, just before the car that is closing the gap gets to me. All this when traffic is very light of course.But trying to find a place to do this on the way to work is proving difficult. I may just pull off on side of freeway and wait for a break in traffic.....
I actually have a very safe place 10 minutes from my house. But it is completely out of my way going to work. I have done some 0-125 mph logs there. Only a couple more days till the weekend........so I will just wait. It is insane even for me to do freeway onramps during rush hour trafficThat's what I do. I wait on the side of the entrance ramp until I see a break in traffic, then slowly get into third. I ease along in third at about 1200 rpm until the break goes by, then I MASH it, just before the car that is closing the gap gets to me. All this when traffic is very light of course.
Here is another short log on the way to work. My % error seems to be pretty small up high. Curious to see difference when I do WOT in 2nd gear this weekend.
DH
Question:
If my WB is reading lean. This equates to a (+) % AFR error.
But when I copy this error and multipy by % or % -1/2 in the MAF table it lowers the values there.
Shouldn't it raise the value ????? A larger air flow would command more fuel wouldn't it ???? Thus correcting the observed lean condition !!!!!
Anyone want to straighten me out on this
DH
If your AFR Error% is (+) (running lean) that means you need to "add airflow" to the MAF cal so that it calculates the correct amount of airflow and thus fueling. Remember the MAF is on the Airflow tab.
If the "measured" aiflow is too low, you get a lean condition, if the "measured" airflow is too high, you get a rich condition.
Always Support Our Troops!
...but, wouldn't "adding airflow" make the values in the table larger (more grams/sec)? I hope this is correct because my numbers are about 45-50 grams/sec higher than they were stock.If your AFR Error% is (+) (running lean) that means you need to "add airflow" to the MAF cal so that it calculates the correct amount of airflow and thus fueling. Remember the MAF is on the Airflow tab.
If the "measured" aiflow is too low, you get a lean condition, if the "measured" airflow is too high, you get a rich condition.
Howie was "adding airflow" and it lowered his values.
Last edited by 2000C-5; 03-23-2007 at 05:16 PM.
The MAF sensor outputs a Hz signal. The MAF airflow table then converts this to a g/sec value. So if the MAF is giving 7500Hz, that would translate in the airflow table to say 50 g/sec. But if your actually getting 60 g/sec, your would be lean because the PCM is only supplying fuel for 50 grams of air. So by increasing the MAF table your telling the PCM that more air is coming in, give the engine more fuel.
Tim
GM World Class TechnicianASE Master Auto TechnicianL1 Certification2001 Silverado 6.0L Swap
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