Where have you been pberry? If I could get my Alta carb. cert. my car would pass smog easy .

 

JCW if you want to cut down on the throttle whistle at low RPMs and good sound at high RPMs. Alta if you want maximum SC sound.

I love my JCW w/AMSoil nanofilter...
Used to have a Dinan, but couldn't stand the throttle whistle (which I would have had with ANY CAI except JCW - some cars have it, some don't...