I took some logs of my car today, here is what I came out with:

STFT = 0%
LTFT = 3.5%
O2 = .935-.960mV
MAFT = not used
Throttle Angle = 99.6%

STFT = 0%
LTFT = 7%
O2 = .915-.915mV
MAFT = 5% Lean, Base
Throttle Angle = 100%

Should I up the MAFT to 10% lean on the Base, then fine tune with the WOT settings? I have read the C5Forums DIY for tuning, and from what I gather, I am heading in the right direction. Thanks guys. :thumbup:

 

I would go 5% lean, get at least one hour driving time before you log again, then tune WOT. When you are tuning for WOT, the only reading that you care about is O2. LTFT and STFT are ignored.

 

you take your LTFT avg from every cell (except for WOT).

i like using the avg. from cells 1-15 to determine LTFT avg.
yes you have to put it into excel and avg it yourself..
i think ChrisB made a spreadsheet that will do it for you with some other things

 

Well your last ones look good but it don't make sense..your first runs showed positive ltrims or was that a misprint..?? if you have positive ltrims the computer is trying to richen the car so why would you lean it out..?? in the first you had 3 positve ltrims I assume and you leaned it out 5% and got 7 something about right for 5 per cent leaner..now you lean it out 10 % and get zero..don't make sense ..you should have had to richen base up maybe 5% and then play with the wot to get down to that 890 range with no knock retard..
I do things easier and quicker with my scanmaster.I look at ltrims when driving much safer to look with scanmaster than autotap unless you have a buddy..I then give it part throttle and watch ltrims..they went to about -2 before the headers I just added and went to zero at wot..I ignore them at idle or at decel and don't bother with all that averaging stuff..makes things way more complicated than it needs to be..besides ltrims don't really affect part throttle at all unless they are way the heck out to lunch and then you get codes and mabye engine damage or plug fouling etc..most guys shoot for low negative ltrims as then when the car goes wot the ltrims go to zero.if they are positve it can add ltrims at wot..making it more inconstent to tune supposedly..You could just have a buddy watch your ltrims..engage part throttle but not full and see if they come down to slight negative..I can't understand how leaning it to 10% can not give you even more positive ltrims unless they were negative and you wrote them down as positive..and now I just installed long tubes so have to retune again and my car was running good..no knock retard..maft was at zero base and zero wot actually..weird but true..guess the sum of all my mods before the longtubes somehow balanced out the rich and lean..

 

Mike, I'll pick your brain more at Carlsbad. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

MY99TAWS6, those numbers are correct, but they are WOT numbers only. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> My mistake, I didn't know (at the time) to average the TFTs out. I was mainly concentrating on the O2 values to get the around the "ideal" .890 mV. Since my car like to go rich at WOT, I leaned it out a bit until I met the number. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> I will be starting from square one again, getting base logs without the MAFT.

 

I was told (at LS1.com) that I need to log the averages of the TFTs. How is that done, or is it only by exporting to (say) Excel, then calculating the averages myself? The TFTs I show are not averages, they are at WOT <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> , but the O2 are now fine. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Ok, so check this out (I logged this, this morning) ... I increased the Base setting to 10% lean:

STFT = 0%
LTFT = 0%
O2 = .885-.890mV
MAFT = 10% Lean, Base
Throttle Angle = 100%

I need more input. <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />