Scaling MAF affect PE?
02-20-2005, 02:21 PM
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Scaling MAF affect PE? I have a quick question. If I scale my maf by 1.07 after tuning my ve table to get the trims back in line, does this directly influence my pe vs. rpm table by making it 7% richer too? ex. if I have 1.15 would that be like 1.22 if the maf table was left unchanged? Reason I'm wondering is that my 02 mv's are around 950 at wot and I have my pe set at 1.15. My IFR is stock but my maf is scaled by 1.07. Reducing the ve at wot areas wouldn't help since I'm running the maf right? Any suggestions are appreciated.
02-20-2005, 02:51 PM
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Originally Posted by luv2spd
I have a quick question. If I scale my maf by 1.07 after tuning my ve table to get the trims back in line, does this directly influence my pe vs. rpm table by making it 7% richer too? ex. if I have 1.15 would that be like 1.22 if the maf table was left unchanged? Reason I'm wondering is that my 02 mv's are around 950 at wot and I have my pe set at 1.15. My IFR is stock but my maf is scaled by 1.07. Reducing the ve at wot areas wouldn't help since I'm running the maf right? Any suggestions are appreciated.
02-20-2005, 05:31 PM
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Originally Posted by txhorns281
this would be why scaling the MAF isn't exactly going to be a consistent improvement for all driving conditions... I would say that if you were running lean at WOT before, your PCM was having to add fuel maybe to reach target AFR. I don't know exactly how much by what kind of scaling will do to your PE, but it would suggest rebuilding the MAF curve to stay consisent with SD airflow. That way it's not too variant from what your VE is and won't cause trimming problems!
The problem you now face is that you have introduced a 7% loading of existing engine and transmission torque calculations, not to mention you have just shifted your spark table down by 0.6g/cyl. Thats why I still prefer the IFR method of fuel trimming. Only affects PE and open loop fuelling - but thats easily handled by applying the same scaling factor you originally used for the IFRs.
02-21-2005, 10:02 AM
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Originally Posted by MNR-0
Any changes you make to measurements of airflow will absolutely change your PE settings - everything is related. You can't change one thing without impacting something else.
The problem you now face is that you have introduced a 7% loading of existing engine and transmission torque calculations, not to mention you have just shifted your spark table down by 0.6g/cyl. Thats why I still prefer the IFR method of fuel trimming. Only affects PE and open loop fuelling - but thats easily handled by applying the same scaling factor you originally used for the IFRs.
The problem you now face is that you have introduced a 7% loading of existing engine and transmission torque calculations, not to mention you have just shifted your spark table down by 0.6g/cyl. Thats why I still prefer the IFR method of fuel trimming. Only affects PE and open loop fuelling - but thats easily handled by applying the same scaling factor you originally used for the IFRs.
02-21-2005, 01:16 PM
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I changed my maf by 106 and im running high 11's low 12's on the wideband. I was going to just fix it but now I see there are other issues 
However since I got the ram air hood it it exremely hard to get the ve table negative. If i cover up the holes its easy to get them down. Scaling the maf worked as well but looks like its a problem.
However since I got the ram air hood it it exremely hard to get the ve table negative. If i cover up the holes its easy to get them down. Scaling the maf worked as well but looks like its a problem.
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02-25-2005, 11:57 AM
#8
I put together a small writeup and a spreadsheet that hopefully will give people no reason to multiply their MAF numbers, but to actually calibrate it.
It's really simple, plug in your numbers, and you get a calibration, i even formatted it so it's easy to copy it back to HPT
Let me know how you like it.
http://allmod.net/hpt/
Marcin
It's really simple, plug in your numbers, and you get a calibration, i even formatted it so it's easy to copy it back to HPT
Let me know how you like it.
http://allmod.net/hpt/
Marcin
Last edited by RedHardSupra; 03-02-2005 at 02:35 PM.
02-25-2005, 12:26 PM
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Originally Posted by RedHardSupra
I put together a small writeup and a spreadsheet that hopefully will give people no reason to multiply their MAF numbers, but to actually calibrate it.
It's really simple, plug in your numbers, and you get a calibration, i even formatted it so it's easy to copy it back to HPT
Let me know how you like it.
http://www.allmod.net/hpt/
Marcin
It's really simple, plug in your numbers, and you get a calibration, i even formatted it so it's easy to copy it back to HPT
Let me know how you like it.
http://www.allmod.net/hpt/
Marcin
Where is the spreatsheet? Did I miss the link on the write on where to download?
02-26-2005, 01:25 PM
#15
Please post your results if you can, i'd love to see if/how it helped you guys out.
Any requests for changes/features yet?
so far i've been thinking of making the graph on the Results tab bit more readable, pick different colors/patters so the actual calibration is more visible. What else?
Any requests for changes/features yet?
so far i've been thinking of making the graph on the Results tab bit more readable, pick different colors/patters so the actual calibration is more visible. What else?
02-26-2005, 05:49 PM
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Great work on the spread sheet!!!! I look forward to the automatic ve table!!!!! btw to my understanding regarding tuning the ve tables and the maf tables seem to accomplish the same thing.And I'm aware that there are different methods in tuning that have the same goal. But excluding wot (if its a factor at all) where do these two differ???
02-27-2005, 08:09 PM
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Originally Posted by RedHardSupra
Please post your results if you can, i'd love to see if/how it helped you guys out.
Any requests for changes/features yet?
so far i've been thinking of making the graph on the Results tab bit more readable, pick different colors/patters so the actual calibration is more visible. What else?
Any requests for changes/features yet?
so far i've been thinking of making the graph on the Results tab bit more readable, pick different colors/patters so the actual calibration is more visible. What else?
Well I did my first test calibration, but haven't applied that back to the car as yet. I found that when I copied that whole line (because it wont let you copy just the cells that have a number value) and then pasted that onto the temp page I had some very unusual results. On the output results I had both #Div/o! and ##### fields in it so I was going off the assumption that the ##### fields were also no data. Well when I copied the whole line sometimes I got actual data for those fields were it was showing ##### and other times I got the #####. Bottom line I took the cells that had good values and pasted to the corisponding HZ in the MAF table. It was definatly off somewhat from what the example showed for my car. Whats the deal with #####? I'm going to wait and see what your opinion is on the ##### fields is before I upload the tune to my PCM. Thanks for the help and awsome tool!
02-27-2005, 08:15 PM
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Originally Posted by God Forgives I Dont
Well I did my first test calibration, but haven't applied that back to the car as yet. I found that when I copied that whole line (because it wont let you copy just the cells that have a number value) and then pasted that onto the temp page I had some very unusual results. On the output results I had both #Div/o! and ##### fields in it so I was going off the assumption that the ##### fields were also no data. Well when I copied the whole line sometimes I got actual data for those fields were it was showing ##### and other times I got the #####. Bottom line I took the cells that had good values and pasted to the corisponding HZ in the MAF table. It was definatly off somewhat from what the example showed for my car. Whats the deal with #####? I'm going to wait and see what your opinion is on the ##### fields is before I upload the tune to my PCM. Thanks for the help and awsome tool!