Are these two mods the most likely to produce more MPG, I know you don't buy a truck, especially a hemi for MPG but I'm a student, daily driver, and have no commuter car. Thanks in advance

 

your not going to see anything of real significance...I doubt youll get your money back from saving gas to pay for the cold air intake, and exhaust...and plus after my i put on my exhaust, i drive harder so i can hear it, but dont get me wrong still a good mod to do to the truck

 

You can make a more efficient flow to your intake if you really want. One thing that I am currently testing is running dryer tubing from the fog light vents to the air filter's intake. The tubing came from OSH for ~$5. After 2 tanks, I am seeing about .5 MPG difference, so it'll pay for itself fairly soon. I would say start a log of your tanks, the fuel you put in, and your MPG, then match it up to what mods you do. Keeps a good record and then you can pass the data onto us.

 

A TRUE CAI should actually HURT fuel economy because cold air is more dense and will cause the PCM to dump MORE fuel yielding greater power.

Now some people do see a modest (.5 mpg or so) gain with a CAI because they are actually introducing a greater amount of HOT air from the engine bay which will cause less fuel to be introduced, increasing fuel economy while decreasing performance. But again, very slightly.

Single best MPG mod IMO for the $ is an e-fan...

 

IMO and as hammer said, an E-fan would be best but I also want to add in a tuner and lots of correct maintenance such as plugs, tire pressure, synth oils, air filters, smaller tires, ect.