studying up before I get edit is this info correct?
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TECH Senior Member
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From: Albuquerque, NM
studying up before I get edit is this info correct? I've been adding to my knowledge of LS1edit I was talking to someone and this is what he emailed me to look out for when tuning:
"you can not go by the 02 readings at part
throttle. GM toggles the air/fuel ratio rich/lean/rich/lean several times a
second.
The .1 02 reading you saw is perfectly normal. They toggle from about
800mvs to 100 mvs several times a second. Autotap is so slow (as is efi
live) that you may not see all of the readings that low. Scan tools are
like taking several snapshots of something happening. You can only snap the
camera so fast, and anything between the snaps you won't see when looking
at your pictures. The slower the scan tool, the more data you do not get to
see. The ONLY thing you can use for a reference for the fueling at part
throttle is the fuel trims. That is why the more knowlegable pros use the
Tech2 scan tool.
Ignore the duty cycle and pulse width at high RPMs also, they are never correct. that is not an actual measurement, just some engineer's calculations. Don't know why they even include that in the data stream. Ditto the AIR/Fuel ratio @ WOT. Bogus numbers there also."
I am wanting to learn all I can before I purchase edit and start messing with it. Is this info correct and leads me on the correct path to tuning bliss?
Thanks
"you can not go by the 02 readings at part
throttle. GM toggles the air/fuel ratio rich/lean/rich/lean several times a
second.
The .1 02 reading you saw is perfectly normal. They toggle from about
800mvs to 100 mvs several times a second. Autotap is so slow (as is efi
live) that you may not see all of the readings that low. Scan tools are
like taking several snapshots of something happening. You can only snap the
camera so fast, and anything between the snaps you won't see when looking
at your pictures. The slower the scan tool, the more data you do not get to
see. The ONLY thing you can use for a reference for the fueling at part
throttle is the fuel trims. That is why the more knowlegable pros use the
Tech2 scan tool.
Ignore the duty cycle and pulse width at high RPMs also, they are never correct. that is not an actual measurement, just some engineer's calculations. Don't know why they even include that in the data stream. Ditto the AIR/Fuel ratio @ WOT. Bogus numbers there also."
I am wanting to learn all I can before I purchase edit and start messing with it. Is this info correct and leads me on the correct path to tuning bliss?
Thanks
Kinda yeah. The O2 are inaccurate at anything other than 14.7:1 AFR. Throughout a normal cruise/part throttle they will cycle any and everywhere. Get a wideband setup, $350 from innovatemotorsports.com, reliable, and you can log up to 44min of wideband. Anyway, the Tech2 is not the answer for logging. You can use a predator to monitor, atap, efi live, palm logger, whatever as long as it shows the necessary parameters, Rpm, Mph, O2, LTFTs, Ignition, KR, MAP, MAF, MAFF, Inj Duty Cycle, Inj Pulse Width, ECT, IAT, IAC, thats what I normally log.
I use the LSM Palm has an autotap version or real similar, as well I used to use my Predator - now I need to actually log, and I use the Innovate wideband. These two tools are immensely helpful. That and this forum. Good luck.
Charlie.
I use the LSM Palm has an autotap version or real similar, as well I used to use my Predator - now I need to actually log, and I use the Innovate wideband. These two tools are immensely helpful. That and this forum. Good luck.
Charlie.
On The Tree
Joined: Oct 2003
Posts: 175
Likes: 0
Originally Posted by frcefed98
I've been adding to my knowledge of LS1edit I was talking to someone and this is what he emailed me to look out for when tuning:
"you can not go by the 02 readings at part
throttle. GM toggles the air/fuel ratio rich/lean/rich/lean several times a
second.
The .1 02 reading you saw is perfectly normal. They toggle from about
800mvs to 100 mvs several times a second. Autotap is so slow (as is efi
live) that you may not see all of the readings that low. Scan tools are
like taking several snapshots of something happening. You can only snap the
camera so fast, and anything between the snaps you won't see when looking
at your pictures. The slower the scan tool, the more data you do not get to
see. The ONLY thing you can use for a reference for the fueling at part
throttle is the fuel trims. That is why the more knowlegable pros use the
Tech2 scan tool.
Ignore the duty cycle and pulse width at high RPMs also, they are never correct. that is not an actual measurement, just some engineer's calculations. Don't know why they even include that in the data stream. Ditto the AIR/Fuel ratio @ WOT. Bogus numbers there also."
I am wanting to learn all I can before I purchase edit and start messing with it. Is this info correct and leads me on the correct path to tuning bliss?
Thanks
"you can not go by the 02 readings at part
throttle. GM toggles the air/fuel ratio rich/lean/rich/lean several times a
second.
The .1 02 reading you saw is perfectly normal. They toggle from about
800mvs to 100 mvs several times a second. Autotap is so slow (as is efi
live) that you may not see all of the readings that low. Scan tools are
like taking several snapshots of something happening. You can only snap the
camera so fast, and anything between the snaps you won't see when looking
at your pictures. The slower the scan tool, the more data you do not get to
see. The ONLY thing you can use for a reference for the fueling at part
throttle is the fuel trims. That is why the more knowlegable pros use the
Tech2 scan tool.
Ignore the duty cycle and pulse width at high RPMs also, they are never correct. that is not an actual measurement, just some engineer's calculations. Don't know why they even include that in the data stream. Ditto the AIR/Fuel ratio @ WOT. Bogus numbers there also."
I am wanting to learn all I can before I purchase edit and start messing with it. Is this info correct and leads me on the correct path to tuning bliss?
Thanks
EFILive aint slow!!, you can get O2 updates (and many more parameters) every 100mS, which is the limit of the PCM, not the scan tool, so Tech2 is no faster.
They say you might not see readings as low as 0.1V, Mmm, wanna see some EFILive logs.
They are correct with regards to using the LTFT (Long Term Fuel Trims) to get a picture of the overall fueling adjusments the PCM is making, however, once again, Tech2 is no good for viewing that, as far a I know EFILive is the only scan tool to show you ALL LTFT values in one simple click of the mouse.
Don't you just love 'expert' opinions.
