Mr. Eric,

I'm using CITY VTEC 2005. currently i've installed 2 VS which are RAZO & PIVOT. i'm wonder if i can put another one?i would like to add your DIY VS. 1 more question. my car RPM is not stable.sometime when i stuck at jem or stop at traffic light the RPM will go down..2-3 second later it will up again...if the RPM go down, my car will vibrate like want to die...is it normal for Honda City??can your VS solve this problem?