MAF table tuning question. Effects at WOT?
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Adkoonerstrator
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From: Deep in the seedy underworld of Koonerville
MAF table tuning question. Effects at WOT? Here is what I'm dealing with right now with my truck.
I've done some intake airflow mods and have descreened the stock MAF. First, don't tell me to put a screened MAF back on because it's not going to happen.
I've looked at some EFILIVE logs and the Ltrims are averaging +2% at idle(0-3000Hz), +7% in the 3000-7000Hz MAF range, and +10% in the 7000Hz+ MAF range(WOT). With the trims this high at part throttle I'm getting trims of +10% at WOT. My O2's at WOT are in the high .800's-low.900's(Not bad).
Here is how I want to adjust to get the Ltrims just slightly negative at part throttle and 0 at WOT.
at idle - not worried so no adjustment.
3000-7000Hz(part throttle) MAF range - multiply by 107% to get trims at 0 or slightly negative.
7000Hz+(WOT) - Multiply by +110%. What I'm concerned about is that when the part throttle trims are adjusted to 0 the truck will run to lean at WOT since there will not be any fuel added by the trims. So is multiplying the 7000Hz+ MAF range the right way to add fuel for WOT or should WOT be adjusted in the PE table.
I can see 7000Hz at less than WOT also but, if the MAF is reading over 7000Hz then the trims go to +10% no matter what the conditions are.
Summary of questions
1. If I adjust the 7000Hz+ range in the MAF table will it also add fuel at WOT when the MAF is reading over 7000Hz or will it only add fuel at part throttle when the conditions are right for a 7000+ MAF reading?
2. If the MAF table will not adjust for WOT at all then should I use the PE vs. RPM table to add more fuel for WOT?
If that stuff isn't clear I can send someone a EFILIVE file to check out. It's 24,000+ frames long though.
Thanks
John
I've done some intake airflow mods and have descreened the stock MAF. First, don't tell me to put a screened MAF back on because it's not going to happen.
I've looked at some EFILIVE logs and the Ltrims are averaging +2% at idle(0-3000Hz), +7% in the 3000-7000Hz MAF range, and +10% in the 7000Hz+ MAF range(WOT). With the trims this high at part throttle I'm getting trims of +10% at WOT. My O2's at WOT are in the high .800's-low.900's(Not bad).
Here is how I want to adjust to get the Ltrims just slightly negative at part throttle and 0 at WOT.
at idle - not worried so no adjustment.
3000-7000Hz(part throttle) MAF range - multiply by 107% to get trims at 0 or slightly negative.
7000Hz+(WOT) - Multiply by +110%. What I'm concerned about is that when the part throttle trims are adjusted to 0 the truck will run to lean at WOT since there will not be any fuel added by the trims. So is multiplying the 7000Hz+ MAF range the right way to add fuel for WOT or should WOT be adjusted in the PE table.
I can see 7000Hz at less than WOT also but, if the MAF is reading over 7000Hz then the trims go to +10% no matter what the conditions are.
Summary of questions
1. If I adjust the 7000Hz+ range in the MAF table will it also add fuel at WOT when the MAF is reading over 7000Hz or will it only add fuel at part throttle when the conditions are right for a 7000+ MAF reading?
2. If the MAF table will not adjust for WOT at all then should I use the PE vs. RPM table to add more fuel for WOT?
If that stuff isn't clear I can send someone a EFILIVE file to check out. It's 24,000+ frames long though.
Thanks
John
Thread Starter
Adkoonerstrator
iTrader: (4)
Joined: Nov 2001
Posts: 21,420
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From: Deep in the seedy underworld of Koonerville
Re: MAF table tuning question. Effects at WOT? I think I've answered my own question reading this document. The MAF is only used for part throttle adjustment. PE vs. RPM is used for WOT.
http://ls1edit.slowcar.net/tuning.html
The MAF is only used for part throttle adjustment. PE vs. RPM is used for WOT. http://ls1edit.slowcar.net/tuning.html
