Factory Ford 73mm MAF...
Titled as such to grab your attention...I picked up a MAF housing a few months ago from the junkyard from a 4.6 Crown Vic/Grand Marquis(found the intake duct and housing in the trunk of another car). These meters actually measure almost right on 73mm instead of the 70mm that everybody refers to them as. After reading some threads, I had found that cutting the center bar out destroys the calibration and the whole thing is trash. Also, many people claimed that the stock 55mm mustang MAF would become a restriction before it pegged.
Well folks, those people are WRONG on both accounts. I took down a little casting flash in the MAF housing and cut out the center bar. Then I installed one of my F1ZF sensors into the housing and decided to give it a shot being as I had a MAF adjuster laying around. I fired it up, expecting it to immediately stall, but it didn't. At warm idle, the modified MAF read .88v...my OE 55mm unit read between .90v-.94v at warm idle. Watching my A/F gauge indicated that the car was running slightly leaner at idle.
I took it for a test drive and it ran only a hair richer at full throttle and it was just slightly lazier (going from lean to rich) during tip in. The car woke up big time. My 351w never really wanted to run past 4k rpm and I had always assumed it was my 5.0 HO upper plenum that was restricting it(which it still is restricting power), but it was pulling great, A/F ratio was good and when I looked at the tach...sure enough, it read 4400 and still going strong.
When cutting out the center bar on these housings, the trick is NOT to use the F2VF sensor that typically come in them...you HAVE to use the Fox-mustang sensor.
I guess I'll see what happens when I get my hogged out, reduced runner length, HO upper plenum welded back together and drop in the 24lb injectors. Hopefully I can get around to it within the next two weeks.
Happy modifying,
Don