Gav

Hi,
Ls1b ecu 2002 motor with 224r cam,90mm tb. Efilive v2 scan and tune.
I have an ls1 swap with cats in sidepipes, lambda feedback is now installed was previously olsd.
I need to prepare my car for emissions now. I have 02 feedback working. I dont have knock sensors or maf.
I just need to tune to pass an mot in uk.
I have had an emissions test and lam was 0.997, hc was around 40ppm, but co was slightly high at 0.352, got to be 0.2 at fast idle.
My questions are if i raise the commanded afr from 14.63 to 14.7 how do i do this? I want to run a slightly lean 1.01 1.02 ish mixture (will help with co going down i hope...) with clsd tune.
Also if this doesnt quite get me the results i want to drop my timing a little. I gather without the maf and knock sensors installed i would just be running off the lo spark tables? And is it just a case of lowering these?
I have a cat in each sidepipe and my headers are lagged down to the collectors so i hope this will be hot enough....
Please help, 5 years doing this now in uk and slowly loosing the will....
Regards
Gav

jayyk31

iTrader: (2)

Bump for the op... interested in hearing any info on this as I'm using an '03 p59 auto tune file from an Express van for my t56 magnum. Imo, unless there r hiden files that differ between the auto and manual tunes then I can't see not being able to make an auto tune work for a manual vehicle. I could be wrong and Def hope someone with the experience can chime in.

jimmyblue

iTrader: (11)

To lean out closed loop decrease the O2 sensor target
voltages (I do not know what EFILive calls it, in my
tool it's "O2 Rich/Lean Voltage vs Airflow Mode". I've
seen 350mV come out about right but many trucks
come saying 500mV and can idle about 13.5:1 on
the wideband, closed loop.

But also look to O2 sensor environment, keep them hot
or mixture will swing slow and wide about center giving
you both CO and NOx that the cats can only try to
reduce, and maybe fail to satisfy The Man. Headers
are bad news this way (at least long tubes; shorties,
not a problem). Do what you can to keep them hot.

Might go in with fresh, thick weight motor oil too, old
oil can hold volatiles that add to CO output and thin
oil can more easily hit the combustion chamber in
higher quantity.

I don't think lower timing is the answer. You do that
for NOx and lean HC problems. You can get elevated
HC from either too rich or too lean, incomplete burn
either way. CO+HC indicates rich and more spark
could give more time for the burn to complete. But
if you're flirting with KR then NOx is liable to come
up if you advance timing.