70mm MAF causing backfire and Pop

It took me forever to find this stupid pic... lol

On the left is the stock 55mm tube, middle is the 90mm LMAF, and the right is the 70mm tube. Notice how the diameters are different...
http://www.veryuseful.com/mustang/tech/tmp/mafs-fox-LMAF-94.jpg



Even if the size of what you are calling the 'sample tube' is the same between the 70mm and the 55mm, you still have the difference between the major diameter (55 vs. 70).
In order for the electronics to be accurate in both of these applications...
They MUST have different output 'calibrations'



jason

Jason is spot-on bud. Some of this stuff seems like it does ok, but it isn't right.

The worst part is that you'd be inclined to run lean since (as Jason said) you're ingesting more air than the computer thinks.

true, the 70mm prolly is calibrated for this too lol, oh well no prob!!

Exactly, the engine should be lean with the early sensor in the later housing.