Throttle Body Spacer?
 

How much difference does or will a throttle body spacer make?
Does anyone have one installed?
Does it make much of a power difference and or gas milege?

This is going to be another funny thread. Don't do it, it will not do shit for your car. The engineers at BMW didn't deem it necessary, I guarantee, it will not do anything.

Nice, thanks for the heads up. I'm guessing a cold air intake would be on the same lines?

By itself no...but included with other tuning options/software etc...then yes, you may notice a difference, depending on which motor.

Any experience with the "Jet Performance Computer Tuning"? On a 4.4L

any single modifications done to these motors will not yield any noticeable gains. if you want more power you will have to use forced induction or purchase a "package" of mods ie: exhaust, intake, throttle body and software. either way you'll have to pay to play.