yobabiesdaddy2001

iTrader: (20)

On the Main spark table (cylinder airmass vs engine speed) what cylinder vs engine rpm combination does your car grab its timing from?

The reason I ask is because I thought that you would alter the cells in the .56-1.20 cylinder mass too 3200-8000rpm, but instead I found that it grabs timing from 0.08-0.24 cylinder mass too 2200 rpm and up.

foff667

iTrader: (2)

it interpolates from the cooresponding cell from the high octane table for the most part, but can be altered somewhere in between that & the low octane table depending upon the knock learn factor.

foff667

iTrader: (2)

oh and then I forgot all the multiplyers & adders that can come into play for ECT, IAT, a/f ratio, etc.

yobabiesdaddy2001

iTrader: (20)

ok, well if you had both tables set to the same degrees, what cylinder airmass vs rpm does the pcm grab the wot timing from?

Or maybe I should ask, does the cylinder airmass drop as rpm increases durning wot conditons

yobabiesdaddy2001

iTrader: (20)

that would have been my next question. What if you delet all of the rest of the other options you mentioned ( iat,ect, ext.....)

RedHardSupra

iTrader: (1)

cylairmass follows torque. you dont want to 'delete' anything as that provides vital information to calculate the cylairmass correctly

yobabiesdaddy2001

iTrader: (20)

well in that case cly air mass would drop as rpm increases. Peak torque = peak efficency.
Still unanswered , where do you guys alter your wide open throttle timing tables? what section of the advanced table?

RedHardSupra

iTrader: (1)

there is no wide open only timing table. airmass changes with temps/altitude/pressure, thus depending on how good conditions are, it will change, that's why the timing table is large, so no matter what the airmass ends up as, you can account for it and give it proper timing

yobabiesdaddy2001

iTrader: (20)

Great explanation,
so depending on temps , altitude and pressure (atmosphere) you could be tuning one section of the timing table one day in Denver on the dyno, and then another section for say Arizona given the same rpm.

chrisj6

Mine has hit as high as .80 on the table before, but at peak torque it mostly is in the .76 range. Thats on a exhaust/intake only 5.3L. It gradually increases and then flattens out in the .72-.76 range around 4000 rpm, after peak torque around 4600 rpms, it falls back off to around .68. Is that more of what you were asking?

chrisj6

Mine has hit as high as .80 on the table before, but at peak torque it mostly is in the .76 range. Thats on a exhaust/intake only 5.3L. It gradually increases and then flattens out in the .72-.76 range around 4000 rpm, after peak torque around 4600 rpms, it falls back off to around .68. Is that more of what you were asking?

yobabiesdaddy2001

iTrader: (20)

yeap, just trying to get a general idea of where everyone was at, location and value wise.

chrisj6

I am hitting mostly 27-29* at and past peak torque. I have found that dipping the timing at peak torque actually lowers gram/cyl in my truck. In your car, a good value to shoot for would be 24-25* at peak hp.