does an intake really make a difference in performance?

 

Yes. Does it take a half a second off your 1/4 times, no.

 

u gain performance after in second , third, and fourth gear
no gain in first gear.

 

I'm half convinced that the intake just makes my car sound faster.

 

intake makes a difference,even a custom job. my most noticable gains were MPG went up significantly. guess that means the throttle was depressed less meaning my engine was being more efficient - sounds like a good display of power increase to me! also they've been dyno'd numerous times and show gains of a few hp up to like 10 or 12 at some points in the RPM range. go to nissanperformancemag.com and read about their installation of an intake on their 3.5 altima. they had a nice dyno of it too

 

It makes a bigger difference on the 2k2/3 than on the 2k/2k1. The airbox is big enough on the 00/01 so that an intake has minimal gains. On the 02/03 the extra .5 liters allows the engine to take in more air, so the stock intake isnt big enough. The thing is, the 00/01's benefit more from a Y pipe than the 02/03's. I guess the exhaust is that much more restrictive.