Intake only improve sound?
 

Just curious how the Stillen or Injen intakes change the sound of the car with stock exhaust?

I have the Stillen Intakes and have the stock exhaust(still saving up F.I. Exhaust)and I don't hear much difference until I get higher revs. Even then, it just sounds...like VRRRROOOOOOOMM<--if you can roll your R's then that's pretty much it.

I think it's a pretty significant difference under WOT and over 5k RPM. It's a great sound under those conditions. Under regular acceleration and under 5k, it doesn't sound any different at all.

I was able to hear my car with the Stillen G3 intakes being run at WOT on the dyno and the first large amount of intake noise is around 3,500-4,000rpm. It then settles out and stays the same until you hit 6krpm and then the intake noise really gets more pronounced. Bottom line is that it really changed the character of the car in my opinion and makes it sound much more aggressive. You will definately notice it immediately with a quiet stock exhaust.

I have Injen CAI, but I installed those when my car was already with FI exhaust so in front of exhaust you can hear them at all. Even with hood open revving the car the sound is not that notable.

I will also add that when I first installed my Stillen Gen3 intake (stock exhaust/cats) it had a very noticeable growl throughout the RPM range, obviously being louder in the higher RPMs. It was awesome. After about 2-3 weeks that additional low-RPM growl was pretty much non-existent, so I assume it took a week or so to settle/burn-in.

Definitely a good first-mod because if you add it AFTER an exhaust you won't hear it at all in my opinion. With my CBE/HFCs there's no way i'll hear the intake even at 7k+ RPM :)

makin a parenthesis, to wash the filters of the stillen gen3 intakes you have to take out the bumper right??

Yes, but trust me it takes all of 10 minutes to remove the bumper after you do it once or twice. I have never removed the bumper on the Z before my Stillen G3 install and even then, it took me 30 minutes at most.

^^^ and the last question: what is the difference in performance between the gen2 vs gen3???