Originally Posted by turtle64b

1. On a hybrid tune, talking with Seb about potentially going straight speed density if the flow/MAF issue can't be resolved and significantly impacts the engine performance/safety.

1a. I have the Omni 4-bar sensor recommended by Seb for this application in the stock MAP sensor location, back driver's side of the manifold.
Seb recommended I use the SpecialtyZ MAP sensor.

https://specialtyz.com/shop/370z-g37...ensor-kit.html

2/3. Looking in to straight speed density.
You'll be better off. Seb prefers to rely on MAFs but even he's telling me he's finding it hard to tune the SC setups as a hybrid tune. Fortunately for us he also knows how to do a good SD tune, just means more work for him unfortunately.

4. The only issue with that is the running really rich if you send the higher-flow signal to the ecu. Since flow is not balanced, you really need the average flow from both branches for it to be accurate. Could splicing the wires together cause damage since the voltages would not be equal? Once you get into electronics that small, even small voltage irregularities where they are not supposed to be can be bad.
Correct, but that is why when bridging the signal you rely on the AFRs to dial back appropriately, once you're confident what the flow characteristics are under low throttle conditions. Under medium to heavy throttle as I mentioned the flow equalizes across both almost instantly (at least my ECUTek logs showed this), which effectively renders the bridge pointless from there on. It's main purpose really is for helping under normal driving, and low throttle conditions. In addition, with a hybrid MAF/SD tune MAF readings are only used for low throttle conditions, SD takes over for medium to heavy throttle.

5. I didn't really look into the logs until now since the car seemed to be running fine. The MAF disparity existed even while the car was running fine under previous tunes, which is weird. I'm thinking that maybe the increased airflow from the 9lb pulley and the Si trim impeller may have caused the greater disparity and therefore made the car perform worse?
Oh absolutely the increased airflow from both those mods is going to cause you grief. I only have the smaller '9lb' pulley and had issue due to flow with normal driving conditions. It lives for full WOT. I have a feeling even more issues would be solved by adding a second BOV, it's almost like it's just not venting enough unwanted boost causing issues with MAF readings, but that's just a personal theory.

6. How did you find the tear? I am trying to avoid tearing down if possible... Trust me, I ill not hesitate to do what must be done, I just feel like an air leak happening all of the time would show in the car idling higher or something like that. At my wits end, and process of elimination, all the symptoms pointed to a leak and I checked absolutely everything else. So took a chance and it paid off.