FOMOCO466

I removed the bottle neck off of my stock intake tube and I think I can feel a big diff... I just filled my truck, and on the last tank before removing the intake part I got 425.3 miles to the tank about 10 miles after the low fuel light came on. That was a trip to richmond up and back @ 245 miles.. the rest was in town, back and forth to work. I've got a 08 FX4 screw short bed with 3:73 and 20's, stock ecu, air filter, 2 in level kit,2300 miles. I'm wondering if it'll do better with that taken off. I don't notice much in the sound under the hood, but a bigger opening can't hurt right. It just popped off with a screwdriver...does that much air go under the fender instead of the engine bay? I have a CAI on hold for me till I can get the $ to pay for it... but I think it's the 3 1/2 and I've heard on here that you have to reprogram stuff if you go that big.... I want better mileage and sound.... but it comes slow for now...Need to do some LED swaps, lol

Is it in my head or can doing something so small help that much? Why doen't Ford make them that big from the fender in the first place?

fitz888

I did the same thing but replaced bottle neck with 3'' pvc pipe and put a k+n drop in filter.Its a little louder but no gains in mpgs.Yes the opening is 3.5 inchs and yours will be full of leaves,trash etc if you dont cover it with something.

JethroTull

yep leaves are a bitch happens to mine after i popped the bottle neck off about 7 months ago now truck has been running like its breathing better eversince

FOMOCO466

wonder what i'd get into making the hole in the fender bigger for a larger tube... that would keep the leaves out right.... or install something over the fender.... maybe an elbow and a fitting right at the core support to work sorta like RAMAIR, hmmmmmm

JethroTull

i mean i guess you can just slap a piece of mesh screen over it life race cars coarse grate mesh so it keeps leaves out but your car still breathes

rplatt56

I did this mods on my 07 5.4 and noticed a .5 mpg increase in mileage

fitz888

Ive tried a few different things but its hard to find 3.5'' pipe or flex hose.One time i used 4'' rv flex hose for rv ****ters i guess ,you can get it at hardware stores its like drier hose but made of a poly material.I ran it behind drivers side headlight down behind tow hook but it looked awfull so I took it out.