Have the stillen intake installed. I just wanted to get an idea if what I am hearing is normal. Between 2600-3900RPM when hitting the throttle I hear a slight high pitch sound (similar to a turbo type sound) before the growl begins. Is that slight high pitch sound a normal with a Stillen Intake and everything else stock?

Thanks!

 

I am to lazy to find out what it is. My sound is only like from 2000-2600 rpms.

 

It is normal. After a while you get used to it.

 

I hear a similar, although more muted sound, with the CAI. Its a a slight sucking, whistling sound. To me it sounds like a very quiet blow off valve.

 

It's normal, just air rushing past the throttle body causing a whistle. It changes as you push on the gas pedal. I can still notice it even after I put the stock intake back on, just not nearly as obvious.

 

when you hear the suck / slurp it gives you some idea just how much air the engine is actually pulling in when you hammer it. pretty impressive, these internal combustion engines - easy to see why lessening the restriction can help so much.