Quote Originally Posted by Fast355 View Post
I am NOT wrong! I have personally witnessed that style MAF as well as the earlier LT1/Vortec/LS1 MAFs do the same thing. The one in particular, I swapped the stock intake tube and box back on to and proved the MAFs (tried 2 different ones) were just fine. I then stuck an 04 LS1 Vette MAF curve in it and it worked with only slight adjustments needed. 5.3L with a 10" long straight 3.75" coupler off the throttle body into a cone filter on a vehicle with very limited engine compartment space. GM uses that same MAF with numerous different airflow tables.

If what you said is correct, this would not happen. The only thing wrong here even was a missing air cleaner element. Fuel trims went +20% the moment the stock air box was mistakingly installed without a filter. Fuel trims were a little off with the open sensor end as well(probably from the mechanical fan blowing air across the sensor) Filter in place and they were sitting near perfect.
https://youtu.be/m-qJ58scPJE

My 4" cartidge MAF has a slightly modified GM Performance Crate 525 HP LS3 MAF curve but I need to add a flow straightner to it.
if nots not a lot of work, would you mind sharing a file with this MAF curve?

i plan to run the cartridge MAF (LS7?) in a 4" tube and would be tickled to have a base curve to start tuning with. Thanks.