Surge right off idle???
04-03-2008, 12:29 PM
#11
I have to agree with Wilde on this one when adjusting the VE table. When I put my new heads on it leaned me out and the MAF wasn't able to correct for it so I had to adjust the MAF table but that was also due to me porting the MAF to 85mm.
If you're using a wideband, you should log in open loop. I'm assuming you are since you're able to read AFR. You don't want fuel trims to interfere with the w/b reading. You want to determine the actual % error between what you're commanding and what the w/b says your tune is actually delivering. When they match +/- 1%, you're done. You can use the MAF histogram in your tuning S/W tuning with a wideband and copy them to the MAF table in your tune and multiply by % until the non-PE portion of the MAF table is within 1-2% rich. The PE portion you want at 0 so that your PE afr is dead on.
If you filter your MAF histogram to ignore afrs greater than 14.5, it'll show you which MAF Hz cells you've zero'd out that you can now multiply by 1.015 to give you a bit of safety in normal use. The trims will zero it out as necessary in closed loop. This is the quickest way for me to get the tune back in line after a head or port job. It's tough to try and tune over the net without actually looking at your tune and vehicle.
If you're using a wideband, you should log in open loop. I'm assuming you are since you're able to read AFR. You don't want fuel trims to interfere with the w/b reading. You want to determine the actual % error between what you're commanding and what the w/b says your tune is actually delivering. When they match +/- 1%, you're done. You can use the MAF histogram in your tuning S/W tuning with a wideband and copy them to the MAF table in your tune and multiply by % until the non-PE portion of the MAF table is within 1-2% rich. The PE portion you want at 0 so that your PE afr is dead on.
If you filter your MAF histogram to ignore afrs greater than 14.5, it'll show you which MAF Hz cells you've zero'd out that you can now multiply by 1.015 to give you a bit of safety in normal use. The trims will zero it out as necessary in closed loop. This is the quickest way for me to get the tune back in line after a head or port job. It's tough to try and tune over the net without actually looking at your tune and vehicle.
if you are a beginer. Not user friendly at all. The only table I can find that has anything to do with the mass air flow sencor is the HZ calabration. If they just had more detail on what each table does I could figure it out. I also don't understand how Cylinder airmass, RMP, and LB per minute relate.
04-03-2008, 07:37 PM
#12
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Gm/Cyl = (MAF in gm/sec * 15)/RPM
MAF in lbs/min * 7.560 = gm/sec
MAF in gm/sec * .1323 = lbs/min
That is the table you use to tune for the MAF. The MAF reads in HZ and that table converts it into an Air Flow for the PCM. Makes sure to keep a copy so you have something to go back to. You want to maintain the curve or so I have read so you might want to scale the whole table up or down a little to see what happens. I have not been brave enough to play with mine yet but I think the time is getting near. Playing with my IFR right now to get my LTFTs as close to zero or slightly negative as I can first.
MAF in lbs/min * 7.560 = gm/sec
MAF in gm/sec * .1323 = lbs/min
That is the table you use to tune for the MAF. The MAF reads in HZ and that table converts it into an Air Flow for the PCM. Makes sure to keep a copy so you have something to go back to. You want to maintain the curve or so I have read so you might want to scale the whole table up or down a little to see what happens. I have not been brave enough to play with mine yet but I think the time is getting near. Playing with my IFR right now to get my LTFTs as close to zero or slightly negative as I can first.
Last edited by Mort; 04-03-2008 at 07:47 PM.
04-04-2008, 04:29 PM
#13
I have to agree with Wilde on this one when adjusting the VE table. When I put my new heads on it leaned me out and the MAF wasn't able to correct for it so I had to adjust the MAF table but that was also due to me porting the MAF to 85mm.
If you're using a wideband, you should log in open loop. I'm assuming you are since you're able to read AFR. You don't want fuel trims to interfere with the w/b reading. You want to determine the actual % error between what you're commanding and what the w/b says your tune is actually delivering. When they match +/- 1%, you're done. You can use the MAF histogram in your tuning S/W tuning with a wideband and copy them to the MAF table in your tune and multiply by % until the non-PE portion of the MAF table is within 1-2% rich. The PE portion you want at 0 so that your PE afr is dead on.
If you filter your MAF histogram to ignore afrs greater than 14.5, it'll show you which MAF Hz cells you've zero'd out that you can now multiply by 1.015 to give you a bit of safety in normal use. The trims will zero it out as necessary in closed loop. This is the quickest way for me to get the tune back in line after a head or port job. It's tough to try and tune over the net without actually looking at your tune and vehicle.
If you're using a wideband, you should log in open loop. I'm assuming you are since you're able to read AFR. You don't want fuel trims to interfere with the w/b reading. You want to determine the actual % error between what you're commanding and what the w/b says your tune is actually delivering. When they match +/- 1%, you're done. You can use the MAF histogram in your tuning S/W tuning with a wideband and copy them to the MAF table in your tune and multiply by % until the non-PE portion of the MAF table is within 1-2% rich. The PE portion you want at 0 so that your PE afr is dead on.
If you filter your MAF histogram to ignore afrs greater than 14.5, it'll show you which MAF Hz cells you've zero'd out that you can now multiply by 1.015 to give you a bit of safety in normal use. The trims will zero it out as necessary in closed loop. This is the quickest way for me to get the tune back in line after a head or port job. It's tough to try and tune over the net without actually looking at your tune and vehicle.
#1 How do I lock it in open loop?
#2 What is the Histogram, and where do I find it?
#3 I also don't know which MAF table you are talking about, and what to multiply by 1.015 %.
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