I am running the XFI and have switched over to running a dry system so that I can have a second stage of Nitrous. I have had good results with the first stage. When I tried to use the second stage the computer energized the the second set of noids, changed timing but did not add the fuel. I am using the PA fuel table as additive which worked for the first stage just fine. I am adding about 85 lb/hr for the first stage then 40 lb/hr on second. The way it acted it seemed like when the second stage activated the additive dropped down to the 40 instead of adding 85 and 40. It back fired and fireslotted the head, not a happy camper! I was understanding that the second stage was supposed to be added to the 1st stage as accumulative action. Any ideas would be helpful. I am going to have some time to think about it while I fix my head! I tried to post the log and tune but wont let me for some reason.