I have been running my car MAF only for a long time, and it has run great like that. I was running a 3 1/2 inch pipe with the maf in a pretty standard spot ( see pic below) and all was good. For reasons that are not important, I had to make a new IC to TB pipe. I decided to go from 3 1/2 to 4 inch and to move the maf to a different spot, (picture below) thinking maybe it would be smoother than it was before.
The new design is basically not tunable to my satisfaction. The car runs great, but has a small hesitation (lean spot) off idle and light surging at cruise.
I tuned the VE to perfection and when in VE only, the issues are not there. I would consider going SD except I have never found a clear answer on the relation of maf and/or VE to torque reporting. My car is a 6L80 and I don't want to take a chance of a change to SD screwing with the trans.
The real question I have is..... would the issue be due more from the different maf placement, the larger pipe, or a combination of both. I can change one, or both back to what they were before if needed, but would like to know which is really the culprit.
Thanks....
New setup....
4 inch pipe (2).jpg
Old setup....
1137179D-74AE-4714-AE1F-65951B9E9856_zpslwu6emvh (1).jpg