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RacerChris
June 15th, 2007, 06:37 AM
I was told to post this question here as well as where I originally posted so that I could get some feedback from the COS guru's.,

I am nearing the end of my AutoVE tuning..... I think...:cheers: But I have a few questions.... In the tutorial it states not to perform the last steps if you are running COS3 or later, (im running COS 5) Why would I not want to return the computer to closed loop speed density? Is there any benifits to doing this or is there a specific reason you shouldnt? Also... By not doing this is there anything that should be changed back to stock perimeters in the original tune, (cat protect, PE, ect...). By not changing back to closed loop speed density am I continually tuning the engine by viewing WB data and adjusting the VE table or are ther other perimiters I should tune???? (spark, throttle cracker, ect..)

Sorry for so many Q's at once but I am just trying to figure this thing out!:)
Thanks again guys!
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joecar
June 15th, 2007, 07:29 AM
You can run semi-closed loop by setting cells in B3647 to EQ 1.00, as said in another thread by KB and SSpd; this trims the AFR to stoichiometry using the STFT and NBO2's; when you do this, your wideband AFR will look like a periodic low amplitude squiggle centered on stoich.

Be sure to keep the high MAP columns of B3647 sufficiently rich to make power and avoid ping under load

RacerChris
June 15th, 2007, 12:55 PM
You can run semi-closed loop by setting cells in B3647 to EQ 1.00, as said in another thread by KB and SSpd; this trims the AFR to stoichiometry using the STFT and NBO2's; when you do this, your wideband AFR will look like a periodic low amplitude squiggle centered on stoich.

Be sure to keep the high MAP columns of B3647 sufficiently rich to make power and avoid ping under load

So to tune for additional power I should add fueling in the high MAP areas right? I am guessing I should just get my VE back to being spot on in those areas and then to richen it up just add fuel via B3647 instead of lieing to the computer and telling it that its more effeciant at filling cylinders at those MAP columns than it really is, Am I on the right track???
Thanks again guys for all the help! I couldnt have got this far without it!

RacerChris
June 15th, 2007, 12:56 PM
One other thing.... How rich should I go in the High MAP areas?? I assume its as rich as I want untill it starts bogging down but I just wanted to be sure.

joecar
June 15th, 2007, 02:43 PM
So to tune for additional power I should add fueling in the high MAP areas right? I am guessing I should just get my VE back to being spot on in those areas and then to richen it up just add fuel via B3647 instead of lieing to the computer and telling it that its more effeciant at filling cylinders at those MAP columns than it really is, Am I on the right track???
Thanks again guys for all the help! I couldnt have got this far without it!I would get the BEN's as close to 1.00 +/- 0.02 everywhere that is reachable;

then, whatever AFR (or EQ) is commanded by B3647 will be what the wideband sees...
this make it easy to set a specific AFR, there's no need to lie about anything... ;)

to make power you need an AFR of high 12's to low 13's...
someone more knowledgeable can give more precise numbers;
I find my motor likes 12.6 (makes power, avoids pinging).

RacerChris
June 15th, 2007, 02:49 PM
I would get the BEN's as close to 1.00 +/- 0.02 everywhere that is reachable;

then, whatever AFR (or EQ) is commanded by B3647 will be what the wideband sees...
this make it easy to set a specific AFR, there's no need to lie about anything... ;)

to make power you need an AFR of high 12's to low 13's...
someone more knowledgeable can give more precise numbers;
I find my motor likes 12.6 without (makes power, avoids pinging).

Thanks Joecar, I figured thats the way it should be done but its better to be sure than to just do it and screw something up. I guess I need to see about tunning on a dyno so that I can get all of those cells nailed!
:rockon: