99whitews6

iTrader: (2)

My commanded AFR is still stock at Stoich from the factory for the part throttle fueling. When I log for the car for a while and then look at the histogram all my part throttle A/F ratios according to the wideband (LC-1) are at 14.9-15.1. Shouldnt they be right at 14.7?

I was wondering if it is the LC-1 that is not configured right or if somehting is wrong in my tune. Whats the easiest way to get this down to 14.7 like it should be.

--i believe my LC-1 is configured (0V=7.35AFR and 5V= 22.39AFR)--

jimmyblue

iTrader: (11)

You're talking a 2% sort of error. That's pretty good in
light of all of the sensor tolerances stacked up. Including
the wideband unit itself.

It's entirely possible that the closed loop trimming (which
tries to make time above, and time below 0.5V even)
results in a different result than 14.7 AFR. But it's also
possible that the meter is just a bit off. You need a
tie-breaker. Does the LC-1 have the same self-cal
(free air) function that my LM-1 does? If so you might
want to let that run one time, and do it in free air (not
in the pipe). Pipe can hold spent gas and mess that up.

If your trims are drifting then it's quite possible that
the LC-1 is telling the truth and you are just not quite
back to proper stoich trimmed mixture. Some peoples'
card are drifting all the time because of messy tune
and trim "bins" that try to cover too much space, so
do none of it well. Like one cell trying to cover off-idle
to 2500RPM, with a stock (therefore, whacked) VE table
up against a big cam. Yeah, that'll be consistently happy
across the drive cycle.

Silverhawk_02TA

I'm assuming you have headers? O2's are heavily dependent upon heat to give an accurate reading, so the AFR that your O2's read as 14.7 when they were in their stock locations is going to be different then the AFR they read as 14.7 when they are sitting much farther down the exhaust path at the end of a set of long tubes. And like jimmyblue said, your wideband is going to have a certain % of error, which may also be playing a role. That being said, 14.9-15.1 is still real close to 14.7, so I'd say you're doing pretty good.

Predator

Even if it was actually 14.9-15.1, there would be no difference, whatsoever, in part throttle performance. The .2 to .4 difference from ideal is probably, as mentioned, the amount of error from the actual reading. Good enough for government work, as they say.

99whitews6

iTrader: (2)

Sounds good. Thanks for the replies guys