02 Rich/Lean
02 Rich/Lean How many people have messed with the 02 switching and had some success? I've heard some say that you should reduce these a little if you have LTs. Can anyone clarify?
I know that Jimmyblue has posted some good info. Do a search.
I'll have some results over the next couple of weeks. Also, via horist's HPT website, I've noticed that pro tuners drop switch points about 50 to 75 mV for headers.
Perhaps the air/fuel charge that blows past the ex valve at low rpms gives the O2's a false reading. Cold, which in turn forces the injectors fat.
This is only a closed loop function so probably effects efficiency more then WOT performance.
I'll have some results over the next couple of weeks. Also, via horist's HPT website, I've noticed that pro tuners drop switch points about 50 to 75 mV for headers.
Perhaps the air/fuel charge that blows past the ex valve at low rpms gives the O2's a false reading. Cold, which in turn forces the injectors fat.
This is only a closed loop function so probably effects efficiency more then WOT performance.
Thanks guys... I scaled the nine cells based on the idea that the o2s would be further of at low airflow than at high airflow. I scaled the first cell by 86%, the second by 88%, 3rd 90%, etc, maybe with a tweak by hand here and there. So far it seems to have helped. Ill have to see over the next few days, though.
My tables look like this now:
315 384 392 401 424 481 491 525 535
Does that look okay to you guys? Im definately polluting less at traffic lights
My tables look like this now:
315 384 392 401 424 481 491 525 535
Does that look okay to you guys? Im definately polluting less at traffic lights
Originally Posted by GuitsBoy
Thanks guys... I scaled the nine cells based on the idea that the o2s would be further of at low airflow than at high airflow. I scaled the first cell by 86%, the second by 88%, 3rd 90%, etc, maybe with a tweak by hand here and there. So far it seems to have helped. Ill have to see over the next few days, though.
My tables look like this now:
315 384 392 401 424 481 491 525 535
Does that look okay to you guys? Im definately polluting less at traffic lights
My tables look like this now:
315 384 392 401 424 481 491 525 535
Does that look okay to you guys? Im definately polluting less at traffic lights
Originally Posted by GuitsBoy
Thanks guys... I scaled the nine cells based on the idea that the o2s would be further of at low airflow than at high airflow.
There is probably too much variability between everyones setup (Cam, headers, exhaust) to make this a generalization.
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From: Atlanta, GA
Originally Posted by SSpeedracer
I agree with that based on valve overlap alone. As RPM's rise mass flow effeciency from int to ex valve (AKA VE) decreases and less fuel per stroke escapes. However, long tube headers will increase the scaveging effect at a "tuned" rpm and increase the amount of fuel getting sucked out.
There is probably too much variability between everyones setup (Cam, headers, exhaust) to make this a generalization.
There is probably too much variability between everyones setup (Cam, headers, exhaust) to make this a generalization.
you can take it down to 300 i think i start at 300 then **** up, that helped the idle a bit once it got warm too. Maybe some other folks can post up their aggressive settings, you can program your ecm to run a "lean burn" sorta for a trip if you plan to cruise control a bit by tweaking these down, maybe 1-2mpg better, which can be alot in the city but even more on freeway trips.
i doubt you'll ever do any damage because timing will get pulled on lean detonation and most of us don't cruise at 100mph
well i try not to. LS1 Tech Stories
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Verdad Gallardo I ran emissions test with the switch points set at mV:
150 150 150 150 150 150 320 320 450
HC PPM went from ~50 to 9. I also swapped random tech catalytic convertors to the stock convertors. So, I'm not sure which helped more.... but I passed! NO, CO and CO2 went up but not too much for a failure. ECT maintained at <195F.
I didnt have my wide band connected so I cant confirm the AFR. However, the O2's were reduced at several RPM ranges.
150 150 150 150 150 150 320 320 450
HC PPM went from ~50 to 9. I also swapped random tech catalytic convertors to the stock convertors. So, I'm not sure which helped more.... but I passed! NO, CO and CO2 went up but not too much for a failure. ECT maintained at <195F.
I didnt have my wide band connected so I cant confirm the AFR. However, the O2's were reduced at several RPM ranges.