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dian
December 6th, 2022, 11:12 PM
on the ls1/99 c5 i see differences of up to 25 grams (about 10%) for up to 1 sec. between sae.maf and gm.maf, sae.maf usually being higher. which one to use?

(i never paid attention to this, as im usually runnind sd.)

edit: while were at it, what is gm.etctp? it seems to be lagging behind sae.tp quite a bit.

joecar
December 16th, 2022, 05:52 PM
Use GM.MAF.

joecar
December 16th, 2022, 05:54 PM
SAE.MAF is not quite the same as GM.MAF.

joecar
December 17th, 2022, 11:02 AM
Post log showing GM.ETCTP and and GM.TP and SAE.TP, these 3 are each different.


For DBW use GM.ETCTP.

dian
December 17th, 2022, 09:24 PM
please remind me: what is dbw?

In-Tech
December 17th, 2022, 09:32 PM
acronyms, bleh dbw as far as I know is Drive By Wire, electronic throttle.

dian
December 18th, 2022, 02:41 AM
thanks. have always been using sae.tp (99 c5) but gm.etctp is consistently lagging by about 0.05 sec (on an average). why use that? (it goes up to 100% vs. 99.6% for sae.tp, but i cant see how that would matter.)

from a log (stock tune): sae.maf 264, gm.maf 237, dyncylair 0.66, rpm 5957. should be 262g/s, so i guess sae.maf is closer. difference usually it not so large. another "extreme" point: 182/166 g/s. during a shift gm.maf seems to go higher (234/266. 9), however.

so what is this, a logging phenomenon, how so? same signal, right? (i was logging at 5 hz.)