MAFless tuning question
Thread Starter
Staging Lane
Joined: Nov 2001
Posts: 74
Likes: 0
From: Burleson, Texas
MAFless tuning question Hey, I just got my HP Tuners software and had a question or two. I have unplugged my MAF and started the primary VE tuning, but I have heard that without the MAF the VCM switches to the secondary VE tables. Is this true or not and, if true, how do I go about making sure the VCM still uses the primary VE tables? And if it doesn't use the secondary VE table with the MAF unplugged, when does it ever use it?
BTW, this software is awesome. I am still a bit overwhelmed at all of the data that can be altered, but I am having a blast learning it.
BTW, this software is awesome. I am still a bit overwhelmed at all of the data that can be altered, but I am having a blast learning it.
With the maf unplugged or disabled the the vcm uses the secondary ve table, so you have to make sure you change the secondary when doing speed density tuning. Also, an easier way to make the vcm switch to speed density is to set the maf fail frequency to 0 under engine diagnostics>general instead of unplugging it.
Thread Starter
Staging Lane
Joined: Nov 2001
Posts: 74
Likes: 0
From: Burleson, Texas
Thanks for the help all. So would it be better just to use the MAF when I am tuning the VE tables so I change the primary instead of the secondary? I would just paste over the secondary table with the primary values but I noticed that the primary table has more data due to smaller increments on the MAP axis. Here is the deal, I am not shooting for SD in the end, I just read that you tune the primary VE table first with the MAF disabled and after you get it tuned properly you enable the MAF and tune the MAF. This just seemed like the most logical order to do the tuning. Thanks again.
Originally Posted by Merlin
Thanks for the help all. So would it be better just to use the MAF when I am tuning the VE tables so I change the primary instead of the secondary? I would just paste over the secondary table with the primary values but I noticed that the primary table has more data due to smaller increments on the MAP axis. Here is the deal, I am not shooting for SD in the end, I just read that you tune the primary VE table first with the MAF disabled and after you get it tuned properly you enable the MAF and tune the MAF. This just seemed like the most logical order to do the tuning. Thanks again.
Leave MAF plugged in...yes.
Tune with the MAF...no - disable by setting fail frequency to 0.
Tune primary VE table...no - copy Primary to secondary and tune secondary. Copy secondary to primary, hand smooth, and re-enable MAF.
**Log MAF Hz (freq.) and Dynamic Airflow while tuning VE to have data for MAF recalibration. See http://www.allmod.net/hpt/ for spreadsheet. OR search for soundengineer's spreadsheet that calibrates the MAF based on MAF Hz and learned fuel trims.
Thread Starter
Staging Lane
Joined: Nov 2001
Posts: 74
Likes: 0
From: Burleson, Texas
Originally Posted by SSpdDmon
Cliff notes:
Leave MAF plugged in...yes.
Tune with the MAF...no - disable by setting fail frequency to 0.
Tune primary VE table...no - copy Primary to secondary and tune secondary. Copy secondary to primary, hand smooth, and re-enable MAF.
**Log MAF Hz (freq.) and Dynamic Airflow while tuning VE to have data for MAF recalibration. See http://www.allmod.net/hpt/ for spreadsheet. OR search for soundengineer's spreadsheet that calibrates the MAF based on MAF Hz and learned fuel trims.
Leave MAF plugged in...yes.
Tune with the MAF...no - disable by setting fail frequency to 0.
Tune primary VE table...no - copy Primary to secondary and tune secondary. Copy secondary to primary, hand smooth, and re-enable MAF.
**Log MAF Hz (freq.) and Dynamic Airflow while tuning VE to have data for MAF recalibration. See http://www.allmod.net/hpt/ for spreadsheet. OR search for soundengineer's spreadsheet that calibrates the MAF based on MAF Hz and learned fuel trims.
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TECH Senior Member
Joined: Nov 2001
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From: Lake Zurich, IL
Originally Posted by Merlin
Ok, thanks, that is the approach I am trying to use but I am unable to do a simple copy of my primary table to my secondary table as the primary table is larger so I was thinking I must be missing something somewhere. I will just edit out the lines I don't need for the secondary table. Thanks for the tips
Then do same for 30,40, etc.... from Primary to Secondary took all of about 5 seconds
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Originally Posted by Merlin
Ok, thanks, that is the approach I am trying to use but I am unable to do a simple copy of my primary table to my secondary table as the primary table is larger so I was thinking I must be missing something somewhere. I will just edit out the lines I don't need for the secondary table. Thanks for the tips
I've been reading too much. G/L with getting the bugs worked out. Thread Starter
Staging Lane
Joined: Nov 2001
Posts: 74
Likes: 0
From: Burleson, Texas
Originally Posted by horist
what I used to do is I'd just highlight the entire 20 MAP row, copy, paste into 20 on secondary
Then do same for 30,40, etc.... from Primary to Secondary took all of about 5 seconds
Then do same for 30,40, etc.... from Primary to Secondary took all of about 5 seconds
Thread Starter
Staging Lane
Joined: Nov 2001
Posts: 74
Likes: 0
From: Burleson, Texas
Originally Posted by SSpdDmon
...and I don't even have my tuning software yet. I've been reading too much. G/L with getting the bugs worked out.
I've been reading too much. G/L with getting the bugs worked out. 
Originally Posted by WS6FirebirdTA00
you can get the new hp tuners update for 49 bucks and it uses the primary table
I have a 2000 which has both primary and secondary VE tables.
I have set MAF fail frequency to 0 and confirmed I have P0103
Then I did a whole bunch of logging.
I then took my histogram and modified the Primary VE table.
From this point I copied line by line 20,30,40,etc. to the Secondary VE table and smoothed the graph.
Am I going about this correctly?
Thread Starter
Staging Lane
Joined: Nov 2001
Posts: 74
Likes: 0
From: Burleson, Texas
Originally Posted by JRick212
esplain this please???? I have HPTuners 1.7 Just got it like 2 weeks ago.
I have a 2000 which has both primary and secondary VE tables.
I have set MAF fail frequency to 0 and confirmed I have P0103
Then I did a whole bunch of logging.
I then took my histogram and modified the Primary VE table.
From this point I copied line by line 20,30,40,etc. to the Secondary VE table and smoothed the graph.
Am I going about this correctly?
I have a 2000 which has both primary and secondary VE tables.
I have set MAF fail frequency to 0 and confirmed I have P0103
Then I did a whole bunch of logging.
I then took my histogram and modified the Primary VE table.
From this point I copied line by line 20,30,40,etc. to the Secondary VE table and smoothed the graph.
Am I going about this correctly?
As for doing it correctly, I think you would first copy your lines 20, 30, 40 etc. from your Primary VE and paste them into your Secondary VE - then do the logging and the smoothing. You would do it in this order since you want to tune your Primary table and you need to start out with the same values in both tables. It looks like the way you did it, you were tuning your Primary table based on your Secondary table values. But I wouldn't start over - since you now have basically the same values in both tables, just keep logging and smoothing the Primary and pasting it in the Secondary until you get what you want.
