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eclispe1
February 28th, 2009, 05:02 AM
Hello all,
I have been getting terriable gas mileage for quite some time and I'm not sure if my auto ve tables are correct. I redone them probably five times or so and no incerase in mpg, it is getting around 11 at best. I have recalibrated the lc1 wideband several times as well between all of my logs It is a 99 ls1 Camaro w/ supercharger at 7 lbs boost and meth injection set at 3 lbs of boost and Magnaflow cat back system. Can someone take a look for me and tell me how to correct this as the car got 20 mpg before I started. I run Shell 93, plus octane booster. I have attached the latest log file. Any help would be greatly appreciated!
Greg

joecar
February 28th, 2009, 11:33 AM
Post tune file and some more logs...

Are you running semi open loop (SOL) [LTFT's and FUELSYS indicate non-CL]...?
Cruising STFT's are between 10%-20%, indicating PCM is adding fuel to keep EQ at 1.00...
something may b e wrong with VE table or O2 switch points.

eclispe1
February 28th, 2009, 11:56 AM
I'm actually not too sure what I'm doing. I do know the car runs awesome but it is using a ton of fuel! I think it is in semi closed loop at the crusing rpm's I have it set up that way I believe to try and save fuel.
Thank you in advance for any help you can give me.

johnv
March 1st, 2009, 10:52 AM
you don't appear to be running a 2 bar map sensor as it has not been scaled in C6301.
so boost VE table and boost timing table will not be working.
the last columb (105 kpa) of your main VE table looks way off over 4400 rpm (numbers are to big)
Table B3647 is scary wrong !!!! your commanding over 16:1 afrs above 70 kpa (although PE should be kicking in by then).
Also what injectors are you running ? has the IFR table been modified.
I would be inclined to tune without the meth first, then add meth and add some timing. maybe pull 4-5 deg timing on what your running with meth and go from there.
I personaly prefer to tune useing 2 bar mafless. Better control of fuel and timing in boost.

joecar
March 5th, 2009, 07:19 PM
Your injector duty cycle is exceeding 100%... are you sure B4001 is correct...?

Like johnv said, B3647 is bad, do not run your motor with this... it appears you may be using Lambda units instead of EQ units... in tunetool go Edit->Properties->Display and make sure it is EQ or AFR and NOT Lambda.

For reference: EQ = StoichAFR / AFR = 1 / Lambda where B3601 indicates StoichAFR.

Are you boosted...?

B0101 table looks wrong... usually it follows the torque curve.

joecar
March 5th, 2009, 07:23 PM
If you're trying to do AutoVE, then any cells in B3647 that are set to EQ 1.00 (i.e. stoichiometric AFR as defined by B3601) will give semi-open-loop (SOL) operation, and you can see this in the STFT activity...

during AutoVE, don't set any cells in B3647 to EQ 1.00... instead choose EQ 0.98 or EQ 1.02 to avoid SOL.

eclispe1
March 8th, 2009, 05:22 AM
The car is supercharged. It was set to Lambda so I changed it, now I will start the auto ve process from scratch and see what happens. B4001 is correct, I'm using the stock injectors.

johnv
March 8th, 2009, 09:36 PM
are you useing a 2 bar map sensor ?
as C6301 is not scaled corectly if you are.

I wouldn't think the factory injectors would have anywhere near enough flow for 7psi.

eclispe1
March 8th, 2009, 11:43 PM
I'm using the stock map sensor for now, I'm trying to figure out the correct one for my motor as my trans is being replaced in the next few weeks and I hope to be able to reach the back of the intake from the trans tunnel. I might have to replace the injectors when money permits. I did change b3647 to what the auto tutorial says to so I will see what kind of results I get from that change, I will probably have to wait for the new trans to really do it as I have no 2nd gear right now.

joecar
March 9th, 2009, 02:33 AM
If you were using Lambda units, change to EQ or AFR, close tunetool and reopen it.

Then set B3647 to what AutoVE tutorial says (but do not set any cell to EQ 1.00, see post #6), and redo AutoVE.

johnv
March 9th, 2009, 10:45 PM
The Auto VE tutorial settings for B3647 are for a NA setup, you will want to set the last columb to something like 11.8 for a boosted engine.

eclispe1
March 10th, 2009, 01:02 AM
Thank you, I did not even think about that. I will make the changes and load the program this morning as I'm off work and can play a little bit.

joecar
March 10th, 2009, 06:30 AM
Good point.

johnv
March 10th, 2009, 04:57 PM
May want to lower your timing a little in the last columb of high and low octane tables as well, as the boost timing table in the COS will not work without a 2bar map sensor.