LSJ E85, VE changes question
No offense taken at all, this is a good discussion.
So check this out, i travel a lot and log rental cars from time to time to see what they have fir settings, also see what cars have what tables available.
Most flex fuel vehicles ive driven, you roll it in on fumes, fill with E, bam 10.39 pops up on the register for commanded.
So check this out, i travel a lot and log rental cars from time to time to see what they have fir settings, also see what cars have what tables available.
Most flex fuel vehicles ive driven, you roll it in on fumes, fill with E, bam 10.39 pops up on the register for commanded.
What's the ethanol content going into the tank is the question? Without knowing for sure, it's really tough to assume. Just for the **** of it, try picking up one of those cheap ethanol testers. The next time you get a flex fuel rental, that test the ethanol content and compare the results again.
Maybe I'm wrong, but I'd be willing to bet that the commanded 10.4 is probably close to 75% alcohol content. Plus pull up one of GM's flex fuel stoich tables. E85 even in their table certainly isn't set for 10.4..
Maybe I'm wrong, but I'd be willing to bet that the commanded 10.4 is probably close to 75% alcohol content. Plus pull up one of GM's flex fuel stoich tables. E85 even in their table certainly isn't set for 10.4..
Thanks gang for the discussion and suggestions.
I saw the post where Area47 said "10.3 afr, set it and forget it" I didn't follow the advice of the expert (my bad) but I also figured at least at the beginning, fatter was safer than leaner. I hope to get some kind of ethanol content analyzer in the near future. I used 9.85
"why not tune MAF first?" --- because I am following The Tuning School's method, and they tune VE first. I understand the rationale -- VE is low (air) speed. Start with idle, then move to low speed, then high speed. You should see how many times they warn not to go WOT. I've not been over 4000rpm yet, and nothing but very light throttle.
please understand I'm not defending the method here, I'm only saying I'm following it because I don't know any better
CURRENT MODS ON THE CAR ---
M62 with 2.7 pulley
LS4 throttle body
RAW cai
Ported and single pass LIM
phenolic spacer
Option B
ZZP LT header / catless DP, 3" tube with resonator and muffler
EVAP system deleted
80's (E85)
BRFPS
the base tune is an HP Tune from a local shop, when the car was 3.0 pulley, 42's on gas. I'm just modifying from there.
prior to this VE tuning mess, all I have changed is:
stoich to 9.85
injectors using the Omega5 spreadsheet and 1.7 as the modifer
Throttle body scalar to 4950
torque management
cranking fuel +50% ( from 100% Meth's recent post. It helped startup tremendously)
idle timing advance -- was 10 across the table, I changed a few cells to 15 and tried it, didn't seem to make any difference, so I changed cells to 20, but haven't flashed that one and tried it yet. After I flashed the one with the 15's, I logged idle (MAF not disabled) for a few minutes. Trims were around -15
The Tuning School provides a default config, but in reading on the HP Tuners forum, I found references to other configs not working for the LSJ, and a "here- use this one" so that's the one I am trying to use. I followed their directions to set up the LTFT histo. Also followed their directions on how to disable MAF. Also followed their directions to try to set up LM1 wideband
I was going to attach the tune, the config, and an idle log with the MAF enabled (chart view) but not sure how to attach here -- use "attach image?
I saw the post where Area47 said "10.3 afr, set it and forget it" I didn't follow the advice of the expert (my bad) but I also figured at least at the beginning, fatter was safer than leaner. I hope to get some kind of ethanol content analyzer in the near future. I used 9.85
"why not tune MAF first?" --- because I am following The Tuning School's method, and they tune VE first. I understand the rationale -- VE is low (air) speed. Start with idle, then move to low speed, then high speed. You should see how many times they warn not to go WOT. I've not been over 4000rpm yet, and nothing but very light throttle.
please understand I'm not defending the method here, I'm only saying I'm following it because I don't know any better
CURRENT MODS ON THE CAR ---
M62 with 2.7 pulley
LS4 throttle body
RAW cai
Ported and single pass LIM
phenolic spacer
Option B
ZZP LT header / catless DP, 3" tube with resonator and muffler
EVAP system deleted
80's (E85)
BRFPS
the base tune is an HP Tune from a local shop, when the car was 3.0 pulley, 42's on gas. I'm just modifying from there.
prior to this VE tuning mess, all I have changed is:
stoich to 9.85
injectors using the Omega5 spreadsheet and 1.7 as the modifer
Throttle body scalar to 4950
torque management
cranking fuel +50% ( from 100% Meth's recent post. It helped startup tremendously)
idle timing advance -- was 10 across the table, I changed a few cells to 15 and tried it, didn't seem to make any difference, so I changed cells to 20, but haven't flashed that one and tried it yet. After I flashed the one with the 15's, I logged idle (MAF not disabled) for a few minutes. Trims were around -15
The Tuning School provides a default config, but in reading on the HP Tuners forum, I found references to other configs not working for the LSJ, and a "here- use this one" so that's the one I am trying to use. I followed their directions to set up the LTFT histo. Also followed their directions on how to disable MAF. Also followed their directions to try to set up LM1 wideband
I was going to attach the tune, the config, and an idle log with the MAF enabled (chart view) but not sure how to attach here -- use "attach image?
Last edited by wayfarer; Dec 15, 2013 at 11:01 AM.
Set VE enable/disable to 200/300 rpm respectively.
This means the MAF is the primary fueling factor and it doesnt reference VE tables any longer
The tune maf to reach desired AFR
This means the MAF is the primary fueling factor and it doesnt reference VE tables any longer
The tune maf to reach desired AFR
Running MAF only, or VE only --
Isn't the consensus that running both is preferred? VE at low air speed, MAF at higher, specifically because MAF is poor resolution at low air speed ?
I personally have always come from the school of thought to do just as you stated though. VE for low air speeds, maf for higher air speeds and have always set my calibrations to this (with some exceptions). I personally like setting the VE disable/re-enable to 3600/3500 to incorporate most light highway cruising as well. Again, that's just my preference, you or the tuning school may prefer it somewhere else. It does however take much longer to dial both sets of tables in nuts on as opposed to just a straight up maf tune. This is also partly why I think most prefer to NOT mess with the VE side of tuning. It's just far more time consuming.
One thing you will learn very quickly though, is there is more than one way to accomplish the same thing. Some ways are better than others depending on who you talk to of course, but if done correctly can more or less be just as good (again depending on who you ask mostly..lol).
My biggest concern with running just a straight maf tune is this. If the maf sensor fails, you are 100% dead in the water and the engine will not run for ****. Now on the other hand, of course the IAT sensor and map sensor can fail at any given time as well BUT, if you have both sets of tables dialed in for idle and normal cruising, guess what. The engine will absolutely still run. It might be pissed off at first but it will absolutely run and you will then be able to limp the car home or to a shop.
Again, this is all my own personal take on things.
was just doing some studying, and think I may have found an issue or contributing factor -- the
Dynamic Airflow -> High RPM Disable is set at 1100, and the High RPM REenable is set at 1000
doesn't this mean if I shut off my MAF, any rpm outside of 1000-1100 is not getting input from either the VE or the MAF, Or does it mean that that is the only range where it takes info from both, if theyre both on?
Dynamic Airflow -> High RPM Disable is set at 1100, and the High RPM REenable is set at 1000
doesn't this mean if I shut off my MAF, any rpm outside of 1000-1100 is not getting input from either the VE or the MAF, Or does it mean that that is the only range where it takes info from both, if theyre both on?
Last edited by wayfarer; Dec 15, 2013 at 11:56 AM.
That would be correct. If you're going to disable the maf and dial in the VE table you will need to raise your disable rpm to just past it or right at your rev limiter settings and the re-enable for 100rpm under that. So if your limiter is set at 7000rpm, then set the disable to 7100 and re-enable for 7000. That way you will be purely on VE fueling all the way to your limiter.
That would be correct. If you're going to disable the maf and dial in the VE table you will need to raise your disable rpm to just past it or right at your rev limiter settings and the re-enable for 100rpm under that. So if your limiter is set at 7000rpm, then set the disable to 7100 and re-enable for 7000. That way you will be purely on VE fueling all the way to your limiter.
I could be wrong, but I'm fairly sure that if you failed the maf, ve will still run no matter what the dynamic table says. Banish says to tune ve, because most v8s do not have a maf. So ve is all they have to tune. Also, that default config isn't working, because it is setup for a v8, with 2 cylinder banks instead of 1 like we have. Fuel trims and other sensors get averaged when you use sensor functions and not pids. That's why it's not working properly for you
If you failed the maf, ve will still run no matter what the dynamic table says. Banish says to tune ve, because most v8s do not have a maf. So ve is all they have to tune. Also, that default config isn't working, because it is setup for a v8, with 2 cylinder banks instead of 1 like we have. Fuel trims and other sensors get averaged when you use sensor functions and not pids. That's why it's not working properly for you
EDIT ; from this thread, post #19, from LWRS10 --- http://www.hptuners.com/forum/showth...ght=lsj+config
I did try to change it to include my LM1 wideband
Last edited by wayfarer; Dec 15, 2013 at 12:27 PM.
I understood, but I specifically remember having straight 50s across my ve table. I'm pretty sure that if you delete the ltft sensor on the histos settings and add in the ltft pid, then you'll be able to log ve ft errors properly. Or just force open loop and tune by afr error as mentioned earlier
I could be wrong, but I'm fairly sure that if you failed the maf, ve will still run no matter what the dynamic table says. Banish says to tune ve, because most v8s do not have a maf. So ve is all they have to tune. Also, that default config isn't working, because it is setup for a v8, with 2 cylinder banks instead of 1 like we have. Fuel trims and other sensors get averaged when you use sensor functions and not pids. That's why it's not working properly for you
Joined: 05-15-11
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From: Livonia, MI
study time !
Per the above posts, I need to learn how to set up my config / histos correctly before I try any more revisions. From what I'm gathering at this point, that is my biggest issue right now.
thankfully the car is not my "driver" so it can sit as long as needed for the learning curve.
Per the above posts, I need to learn how to set up my config / histos correctly before I try any more revisions. From what I'm gathering at this point, that is my biggest issue right now.
thankfully the car is not my "driver" so it can sit as long as needed for the learning curve.
sent you an email, told you a good number of things to correct, mostly your injector tables are completely off, I also sent you the injector table made by omega (I think thats who made it). Give me some more time and I'll send you what I can to help you out, let me know if you have anymore questions after you fix the things I listed.
sent you an email, told you a good number of things to correct, mostly your injector tables are completely off, I also sent you the injector table made by omega (I think thats who made it). Give me some more time and I'll send you what I can to help you out, let me know if you have anymore questions after you fix the things I listed.
my question is -- I have seen several references to "copy your high octane table to your low octane table" in tune discussions--
is this a tuning tool, or a permanent change,
and, good idea or bad?



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