LS2 to LS3 MAF help

[tc83]

I swapped to a 6l80 on my gen 4 5.3 and when I ordered the new harness I decided to switch to the ls3 style maf. Can somebody help me change what i need to on the engine side with that? I've already flashed the t43 with my mdi2 I just really don't know what I'm doing with these maf tables and id really rather not pay another 500 to re-tune if I can help it. c10 after mdi reflash.hpt

[tc83]

Even if I have to pay again I?d need to get it so it?s drivable and I can get exhaust put on it and drive it to the shop

[blindsquirrel]

How do you imagine it'd be possible to not have to retune it after changing from one MAF to a totally different one? The MAF table is all about how the air moves in the plumbing, all the way from the inlet to the filter to where it exits into the throttle body, and the MAF is part of that plumbing both airflow-wise and electrically. Just because the engine on the other side of the throttle body hasn't changed means nothing to the MAF table and what it's for.

To make it driveable without the MAF re-tuned, fail the MAF and put it in speed density.

[tc83]

I knew it would need to be retuned I was hoping someone here could help me do that

[obthomas]

I swapped to a 6l80 on my gen 4 5.3 and when I ordered the new harness I decided to switch to the ls3 style maf. Can somebody help me change what i need to on the engine side with that? I've already flashed the t43 with my mdi2 I just really don't know what I'm doing with these maf tables and id really rather not pay another 500 to re-tune if I can help it. c10 after mdi reflash.hpt

I'm thinking you may need to change the vehicle wiring harness because somewhere around 08/09 the MAP pinout changed. I know that the LS3 and some earlier MAP sensors have different pinouts. I have attached a diagram of an LS3 MAP and an escalade MAP and they are different08 escalade MAP.png09 camaro MAP.png

[tc83]

I changed the harness I ordered a new one from psi when I did the swap to the 6L80 its for a ls3 sensor i copied the maf table from my wifes commadore and lowered the high side and interpolated between bounds and that got it to idle its still really rich though

[charcoal03silvy]

IF, big IF, the speed density model is dialed in you can fail the MAF, plot dynamic airflow into a MAF graph with the same axis as the maf table, and run a log to plot your new MAF curve. If SD isn't dialed in, well... not gonna work well.