OLFA vs. PE
04-18-2006, 06:19 PM
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OLFA vs. PE Why does everyone use PE to adjust WOT fueling and don't do anything to the OLFA table?
According to the help section in HP tuners.....
Open Loop Mode
Open Loop F/A vs. Coolant Temp vs. MAP: This table is used to determine the commanded AFR when in open loop mode. It divides the Stoich AFR value. AFR is determined by 14.7/table value. Example: 14.7/1.30 = 11.3 AFR
Power Enrichment
V8 Power Enrich Fuel Multiplier vs. RPM: This is the main table that is used to tune WOT fuel for post 1999 V8 engines. The values in this table are Fuel/Air multipliers (or AFR divisors) ie. values greater than 1 are richer, values less than one are leaner. The values relate directly to the Stoich AFR and the resulting commanded AFR is Stoich divided by this PE multiplier. Eg. if the multiplier is 1.1 then the commanded AFR will be 14.7/1.1 or 13.36.
Shouldn't commanded and actual fueling coincide with each other?
According to the help section in HP tuners.....
Open Loop Mode
Open Loop F/A vs. Coolant Temp vs. MAP: This table is used to determine the commanded AFR when in open loop mode. It divides the Stoich AFR value. AFR is determined by 14.7/table value. Example: 14.7/1.30 = 11.3 AFR
Power Enrichment
V8 Power Enrich Fuel Multiplier vs. RPM: This is the main table that is used to tune WOT fuel for post 1999 V8 engines. The values in this table are Fuel/Air multipliers (or AFR divisors) ie. values greater than 1 are richer, values less than one are leaner. The values relate directly to the Stoich AFR and the resulting commanded AFR is Stoich divided by this PE multiplier. Eg. if the multiplier is 1.1 then the commanded AFR will be 14.7/1.1 or 13.36.
Shouldn't commanded and actual fueling coincide with each other?
04-18-2006, 07:26 PM
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Because there's not trigger to go to the OLFA table like there is the PE table. When you floor it, the enablers point to PE (TPS%, MAP pressure, etc.). Also, PE allows for AFR tuning based on RPM's, which will change across a broader range than MAP pressure will when you floor it. That way, you can command a different AFR for peak torque than you would for peak horsepower (which is what you want to do). The OLFA was designed more as a backup for situations where closed loop is not available (ie startup, sensor failure, etc.).
04-19-2006, 04:28 PM
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Originally Posted by Checkmate
Beware, if OL table is richer than commanded PE you WILL get the richer of the too. 
So, if you adjust your PE to less than 1.13, it won't lean out more?
No wonder leaning out my PE didn't do anything.......
Right now, my PE is back to 1.15 though.
04-19-2006, 08:00 PM
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Originally Posted by silverTA2002
The stock OLFA table is 1.13 at WOT for my car.
So, if you adjust your PE to less than 1.13, it won't lean out more?
No wonder leaning out my PE didn't do anything.......
Right now, my PE is back to 1.15 though.
So, if you adjust your PE to less than 1.13, it won't lean out more?
No wonder leaning out my PE didn't do anything.......
Right now, my PE is back to 1.15 though.
In a perfect world your pe table should be 1.13 (14.7/1.13=13.00)
04-19-2006, 08:44 PM
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Originally Posted by Checkmate
Correct. I discovered this problem on the dyno, I wasted 30 minutes trying to figure out why it wasn't leaning out.
In a perfect world your pe table should be 1.13 (14.7/1.13=13.00)
In a perfect world your pe table should be 1.13 (14.7/1.13=13.00)
Where did you find the perfect world afr of 13:1? I always heard, used, and seen 12.5'ish reporting better results than 13.00. I run mine richer than that to peak torque, and then slightly lean it out, still richer than 13.0:1 for peak HP. In PE I never see something as lean as 13:1.
Not sure I would even mess with the OLFA. If you tune your PE on a nice curve, then whats the need for having OLFA richer to get peak torque? Why not use the PE to richen up peak TQ? I leave my OLFA about .5 leaner than the PE in case for some reason it goes out of PE and into OLFA, MAF Failure or whatever it is, but I will still be rich enough to run the spray. And yes, I run richer than 13:1 NA also.
Original post quotes HPTuners:
V8 Power Enrich Fuel Multiplier vs. RPM: This is the main table that is used to tune WOT fuel for post 1999 V8 engines.
Why ask why?
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04-19-2006, 09:43 PM
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Why ask why? The better I understand how it works, the better I can tune my car.
The more I learn how things "should be done" the more I realize how many people take the "easy way out" and don't touch tables because they don't understand them.
It's one thing to leave certain tables alone because you SHOULDN't mess with them, but another if they're just "complicated" to tune.
It sounds like the OLFA table is a "fall back" if MAF fails.
But, isn't that kinda how the VE table is described? But tuning the VE properly makes a BIG difference. Then again, I don't think there's a part throttle fueling table like PE is for mid to full throttle.
The more I learn how things "should be done" the more I realize how many people take the "easy way out" and don't touch tables because they don't understand them.
It's one thing to leave certain tables alone because you SHOULDN't mess with them, but another if they're just "complicated" to tune.
It sounds like the OLFA table is a "fall back" if MAF fails.
But, isn't that kinda how the VE table is described? But tuning the VE properly makes a BIG difference. Then again, I don't think there's a part throttle fueling table like PE is for mid to full throttle.
04-19-2006, 10:16 PM
#9
Originally Posted by silverTA2002
Why ask why? The better I understand how it works, the better I can tune my car.
The more I learn how things "should be done" the more I realize how many people take the "easy way out" and don't touch tables because they don't understand them.
It's one thing to leave certain tables alone because you SHOULDN't mess with them, but another if they're just "complicated" to tune.
It sounds like the OLFA table is a "fall back" if MAF fails.
But, isn't that kinda how the VE table is described? But tuning the VE properly makes a BIG difference. Then again, I don't think there's a part throttle fueling table like PE is for mid to full throttle.
The more I learn how things "should be done" the more I realize how many people take the "easy way out" and don't touch tables because they don't understand them.
It's one thing to leave certain tables alone because you SHOULDN't mess with them, but another if they're just "complicated" to tune.
It sounds like the OLFA table is a "fall back" if MAF fails.
But, isn't that kinda how the VE table is described? But tuning the VE properly makes a BIG difference. Then again, I don't think there's a part throttle fueling table like PE is for mid to full throttle.
04-19-2006, 10:16 PM
#10
Originally Posted by CAT3
Where did you find the perfect world afr of 13:1? I always heard, used, and seen 12.5'ish reporting better results than 13.00. I run mine richer than that to peak torque, and then slightly lean it out, still richer than 13.0:1 for peak HP. In PE I never see something as lean as 13:1.
Not sure I would even mess with the OLFA. If you tune your PE on a nice curve, then whats the need for having OLFA richer to get peak torque? Why not use the PE to richen up peak TQ? I leave my OLFA about .5 leaner than the PE in case for some reason it goes out of PE and into OLFA, MAF Failure or whatever it is, but I will still be rich enough to run the spray. And yes, I run richer than 13:1 NA also.
Original post quotes HPTuners:
V8 Power Enrich Fuel Multiplier vs. RPM: This is the main table that is used to tune WOT fuel for post 1999 V8 engines.
Why ask why?
Not sure I would even mess with the OLFA. If you tune your PE on a nice curve, then whats the need for having OLFA richer to get peak torque? Why not use the PE to richen up peak TQ? I leave my OLFA about .5 leaner than the PE in case for some reason it goes out of PE and into OLFA, MAF Failure or whatever it is, but I will still be rich enough to run the spray. And yes, I run richer than 13:1 NA also.
Original post quotes HPTuners:
V8 Power Enrich Fuel Multiplier vs. RPM: This is the main table that is used to tune WOT fuel for post 1999 V8 engines.
Why ask why?
04-19-2006, 10:49 PM
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Originally Posted by 98Z28CobraKiller
I was under the impression that the OLFA table was in case of O2 sensor failure. Hence, people use this table that are running SD w/o narrowband O2's and w/ WBO2.
04-20-2006, 04:19 PM
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Originally Posted by 98Z28CobraKiller
I was under the impression that the OLFA table was in case of O2 sensor failure. Hence, people use this table that are running SD w/o narrowband O2's and w/ WBO2.
Nino
04-20-2006, 04:22 PM
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Originally Posted by 98Z28CobraKiller
What about 98 PCM Vehicles
