Some of you might find these guys informative and entertaining.
Others will probably flame me for blasphemy.
They're a couple of Australian guys that work on cars, mod them, dyno the results etc. their dyno shows no improvement with cold air. And another video shows reduced hp with cone filters.
Remember....don't hate the messenger.

 

message has been posted before. thanks though

 

Wait, what?!?!? Throwing an Autozone SPL filter and piping with no other modification whatsoever makes no power?

 

You may gain a little power at the top of the rev range but it isn't as much as is lost on the low and mid range.. The same is true with larger diameter exhaust pipes.. It's a different story when you have boost of over 5 PSI.. I have an Apexi exhaust control valve to quiet down my exhaust when in urban traffic.. Partially closed I have a little more low end pulling power than when it is in the open position... I lost power on the top end in 5th gear as well as on the low and mid with a larger diameter intake and exhaust.. I topped out at 5 MPH less than with the stock setup and my ears were constantly ringing as well.

 

The stock intakes for both GD3 and GE8 fits are ALL cold air intakes. Air flows into the intake systems from outside the engine bay. GD Fits pick up air from an air duct in the driver side fender, and GE's pick up air from a scoop located just below the front edge of the hood, and air is conducted back to the firewall where the stock intake has the inlet for the intake system. Some after-market intakes provide a slight advantage by having less restrictive bends in the system, but pick up air in the same general locations as the stock intakes.

The PRM intake systems, made in Canada for GD's and GE's, make more hp but pick up air in exactly the same locations as stock intakes, using the same fender-well port in the GD3's, and the same firewall location behind the hood scoop on the GE's.