I am pretty unclear about what has to be done to your car for supercharging. I have heard you have to retard the timing for it to work right. I ve also hear that you need custom computer tuning. Does this mean my hypertech will not work anymore? It keeps my speedometer correct. Im interested in the vortech S-trim. Can I just slap this thing on or is there lots of complicated things to do? Please help me. Oh Yeah, I have a 99 cobra with a 4.10, hypertech program, flows, and a KN CAI.