Question about LTFT and how to adjust with ls1 edit
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Question about LTFT and how to adjust with ls1 edit I have a 02 Z06 and have added a Vortex cold air box. I have autotapped my car and my LTFTm's are averaged out at +15. So now what do I do with ls1 edit to change it to a negative number. Some have said to mess with the maf table and others have said to mess with the injector pulse width tables but I'm now confused. What would I do if I added 30lb injectors? I know that messing with the PE table controls wot adjustment. thanks
Launching!
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Re: Question about LTFT and how to adjust with ls1 edit Injector flow rate is the place to play with. I've gone from +25 LTFT to about 0 and after my drive him I'm hoping that they will be slightly negative.
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Re: Question about LTFT and how to adjust with ls1 edit </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by MUSTANG HAT'R:
<strong> Dont mess with the injector pulse width table. Use the injector flow rate table, and thats the same table you would use if you put in bigger injectors. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Is there some postings or website on how to adjust injector flow rate table? There is a write up for the MAF table but I have not read one for the injector flow rate table.
thanks
<strong> Dont mess with the injector pulse width table. Use the injector flow rate table, and thats the same table you would use if you put in bigger injectors. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Is there some postings or website on how to adjust injector flow rate table? There is a write up for the MAF table but I have not read one for the injector flow rate table.
thanks
Re: Question about LTFT and how to adjust with ls1 edit I've adjusted the MAF table and it worked like a charm...just scale it by the percent LTFT you want to reduce...example:
you are at +15 average, and you want -3, then scale the table by 118 (100+15+3) and you'll be really close to -3 LTFT average. When you add mods that let more air in, you need to adjust with more fuel, or you will run lean, causing the LTFTs to be positive because they are adding that much fuel to compensate.
Then go back and look where your LTFTs are -8 and reduce the MAF number for that RPM, and add more to the cells where your LTFT is postive...that way your whole RPM range will provide you with negative LTFTs without being too out of whack.
you are at +15 average, and you want -3, then scale the table by 118 (100+15+3) and you'll be really close to -3 LTFT average. When you add mods that let more air in, you need to adjust with more fuel, or you will run lean, causing the LTFTs to be positive because they are adding that much fuel to compensate.
Then go back and look where your LTFTs are -8 and reduce the MAF number for that RPM, and add more to the cells where your LTFT is postive...that way your whole RPM range will provide you with negative LTFTs without being too out of whack.
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Re: Question about LTFT and how to adjust with ls1 edit Your not going to solve that lean of a condition by just tuning, you need the SVO 30 injectors and then ONLY adjust the injector flow table.
Being your 15% lean and could be leaner in summer heat, assume by using SVO 30s your increasing flow about 30% richer, minus the 15% lean you are, so 1st tune increase flow table by 15% and fine tune from there.
Stay away from mucking with MAF table, it will confuse the PCM even as far as what delivered torque is.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Vortech:
<strong> I have a 02 Z06 and have added a Vortex cold air box. I have autotapped my car and my LTFTm's are averaged out at +15. So now what do I do with ls1 edit to change it to a negative number. Some have said to mess with the maf table and others have said to mess with the injector pulse width tables but I'm now confused. What would I do if I added 30lb injectors? I know that messing with the PE table controls wot adjustment. thanks </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Being your 15% lean and could be leaner in summer heat, assume by using SVO 30s your increasing flow about 30% richer, minus the 15% lean you are, so 1st tune increase flow table by 15% and fine tune from there.
Stay away from mucking with MAF table, it will confuse the PCM even as far as what delivered torque is.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Vortech:
<strong> I have a 02 Z06 and have added a Vortex cold air box. I have autotapped my car and my LTFTm's are averaged out at +15. So now what do I do with ls1 edit to change it to a negative number. Some have said to mess with the maf table and others have said to mess with the injector pulse width tables but I'm now confused. What would I do if I added 30lb injectors? I know that messing with the PE table controls wot adjustment. thanks </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
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Re: Question about LTFT and how to adjust with ls1 edit IFR Table- multiply table by less than 100% to increase flow ( when you have pos trims). This tells pcm that there are smaller injectors and it then compensates and increases flow. Try ~95% initially.Multiply by Greater than 100% to reduce flow ( when you have neg trims).Hope this helps. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
There was a long debate on LS1EDIT.COM last year. Basic conclusion was - Maf is a calibrated sensor, if you haven't changed your MAF (ported etc.),don't rescale it. Use IFR table to adjust fuel -LTFTs. You can follow the debate by searching LS1EDIT archives. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
<small>[ April 15, 2003, 12:47 PM: Message edited by: binksz06 ]</small>
There was a long debate on LS1EDIT.COM last year. Basic conclusion was - Maf is a calibrated sensor, if you haven't changed your MAF (ported etc.),don't rescale it. Use IFR table to adjust fuel -LTFTs. You can follow the debate by searching LS1EDIT archives. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
<small>[ April 15, 2003, 12:47 PM: Message edited by: binksz06 ]</small>
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Re: Question about LTFT and how to adjust with ls1 edit But if i put SVO 30's in it the trims will autmaticaly go into the negative-that's what i did when i had the MAFT and then adjusted WOT. I was trying to do it without the injectors. If i scale the injector flow rate down with the 30's then won't that again put me into the positives for fuel trims?
