i know that the nw 3v motors are very touchy when it comes to airflow so you can end up w/ a 14:1 a/f ratio by changing yoru intake... now is the same true for the 99-04 2v motors?
also which is better to do, C&L MAF/Intake kit or a 2 1/2" O/R H-Pipe?
I have never seen a A/F ratio jump to 14:1 just by switching intakes.
In regards to your 2nd question, it's kinda comparing apples to oranges. Personally I'd get an O/R H pipe AND do a plenum/TB/CAI and leave the MAF alone.
intakes will make you run slightly leaner, but not as drastic as that which you mentioned.
don't waste your money on the maf. you don't need to upgrade unless you're pegging your stock one. front your list, get the hpipe but you should save for gears, and a shifter.
well the C&L kit replaces the MAF housing w/ a larger on and that is part of the intake system... they showed dyno's on a car about like mine making about 8whp just from the maf replacement.
which one first... intake OR exhaust... i plan on doing them all but which is more likely to make it use the fuel it has right now more efficiently.... this coming weekend i plan to LEARN mustangs much as i have done w/ mr2's supra's, SBC's and Honda's so there should be no more dumb qustions from me after this week