injector tuning?
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injector tuning? Just installed 42# injectors and adjusted the flow rate vs. kpa tables via hptuners. It has been running rich and I had to adjust the stoich afr to 16.9 to get it running just right again. Why is it that I cannnot run an afr of 14.7 after I adjusted for the injectors? Is there another adjustment that I have looked over?
Last edited by dankinmydome; Apr 6, 2007 at 11:26 AM. Reason: grammar
someone answer this man!!!! i have same question! i installed 60lbs injectors when i did my heads/cam swap and now i cant get this bitch to idle for ****!!! it is pig *** fat and pulls a ton of fuel at idle and when i try to massage the injector size to make it lean up some, it has no affect at all. why no affect to fuel trims when i raise or lower the injector size?!!!!! come on guys,,,answers!!!!
my idle, cruise , and wot was stock feel and afr when i changed my ifr and min inj pw to =oldifr/newifr X 1.277(stock setting). mine was 0.790 for 37lb lucas injectors.
i had rich decel so i went to transient fuel and changed
1. fuel mg to .005 (stock=.045)
2. min rpm to 3000 (stock=300)
3. boiling vs temp table was reduced 20%.
i had to do all three of these changes together to get rich decel down.
i really don't know exactly what these settings did but the rich decel is under control says the wb. try at your own risk. i have a wb and hope you got one too. good luck because i've been tuning these injectors for 2 months and over 100 tune variations.
oh, i i had to do ve, maf, and spark also.
i had rich decel so i went to transient fuel and changed
1. fuel mg to .005 (stock=.045)
2. min rpm to 3000 (stock=300)
3. boiling vs temp table was reduced 20%.
i had to do all three of these changes together to get rich decel down.
i really don't know exactly what these settings did but the rich decel is under control says the wb. try at your own risk. i have a wb and hope you got one too. good luck because i've been tuning these injectors for 2 months and over 100 tune variations.
oh, i i had to do ve, maf, and spark also.
Originally Posted by dankinmydome
Just installed 42# injectors and adjusted the flow rate vs. kpa tables via hptuners. It has been running rich and I had to adjust the stoich afr to 16.9 to get it running just right again. Why is it that I cannnot run an afr of 14.7 after I adjusted for the injectors? Is there another adjustment that I have looked over?
I use EFILive not HPTuners so bear with me. The IFR vs Manifold Pressure table is not IFR vs MAP. Yes it is the IFR at various pressures and the pressures are in kPa, but the table references IFR vs Manifold Vacuum. Just the opposite of MAP. So I was trying to go richer in what I thought was the low MAP section of the curve. To do that I had to increase the IFR at low MAP. Well I was assuming low MAP was 10-50 kPa........its not. The table is in Manifold Vacuum. So 20 kPa is 80 kPA MAP. And 80 kPa on the table is 20 kPa MAP.
So I was raising the IFR in that wrong end of the table and lowering it in the other end. Voila, as soon as I remembered (or really relearned) that tidbit, I was good to go.
Now maybe HPT beats the EFILive explanation of that table and this isn't your problem, but it had me tearing my hair out all week.
Perry
I have the delphi 42# injectors there are three tables that I adjusted.
1.flow rate vs. kpa tables
2.min injector pulse rate and default injector pulse rate tables
3.And the most difficult the offset vs. volts vs. kpa vac table
I think my #3 table is still a little off but after doing those three then tuning VE and the MAF it runs like a scalded ape! It took some tooling around but I found all the answers on the hptuners forum!
1.flow rate vs. kpa tables
2.min injector pulse rate and default injector pulse rate tables
3.And the most difficult the offset vs. volts vs. kpa vac table
I think my #3 table is still a little off but after doing those three then tuning VE and the MAF it runs like a scalded ape! It took some tooling around but I found all the answers on the hptuners forum!
Originally Posted by dankinmydome
Just installed 42# injectors and adjusted the flow rate vs. kpa tables via hptuners. It has been running rich and I had to adjust the stoich afr to 16.9 to get it running just right again. Why is it that I cannnot run an afr of 14.7 after I adjusted for the injectors? Is there another adjustment that I have looked over?
42lb injectors should be about 84% more flow than the stockers, so increase the IFR table 84%
