I was surprised when I first drove my maxx after the install... I could not hear the SI... maybe because I was allready used to the "bees in a can" sound from my Y-pipe... but none the less... I rolled up my windows... turned off my tunes... and flored it.... Yeeeeeehhhhhaaaa!!! I f*cken sounds like an NSX..... the sound is so subtle (compared to my Honda AEM intake)... but it's niiiiceeee! I did not feel too much of a differance... but I will try tomorrow with some good 92 octane and an oil change.... has anyone done a dyno on the SI alone.