It's been a while since I've posted. Life happens between building and testing new cell designs. I installed a Volo FS-2 HHO in my '96 Jetta this past weekend. It went in smoothly. One of the easiest things I have ever put in a car. I wanted to put a Volo chip in before I put my new cell in to answer a question that has been bothering me: Are some folks getting mpg gains because of the tweaks to their ecu and thinking that the gain is because of their cell? I searched the forums but could not find an answer. My plan is to run the car on the Volo alone without a hho cell and record mileage for a few months. Then install my new cell, reset the chip and run for a few more months combined to see if there is a difference. Stock my Jetta gets 29 mpg.