Like almost everyone has posted your gas mileage won't be helped by a intake or exhaust. It's not the fault of either, it's all about what goes on between what you're hearing/brain/right foot. We love the sound of power that equates to lower gas mileage. If you're that concerned about gas mileage maybe you shouldn't be driving a G35 anyway!
Gary

 

Yep.. it's all about over 3k rpms.. the sound it makes will make u want to hear it all the time.. Just find a nice gas station u like going too hehehe

 

In theory, it's suppose to increase your mpg since the air ratio should be higher.
However, you'll probably step on the gas more.

You can't really compare until you are used to the intake and start driving normal again.
On my old Eclipse, I had a 1-2 mpg gain with AEM CAI driving on the same freeway everyday going very gently.

 

He just wants to know if getting intake help increase MPG, doesnt matter about if u want to go over 3k RPM just to hear the sound growl and punching it to 3k rpm everytime...
Yes it does help you increase MPG slightly for normal drive.

If you want to save more on gas it just depends how you drive you car too

 

thanks ____

lol