I noticed on one of your poat that you were riding a warrior and running the Big Gun exhaust with a 147.5 main. I called Big Gun to order the slip-on and they told me to run the 150 main. Did you try any other main jets? I live in Dallas which is about 700 or so feet above sea level. I have the Pro Flow filter kit but I'm running the stock air box with lid and snorkel. Last, did you notice a big difference with the Big gun? Where bottom, mid, top end?