Thanks guys, I wasn't positive that Enya only made AAC. I have run in many ABC engines and didn't know if there was anything different required or not. I am running a stock OS muffler and plan to start off with an APC 11x7 and 10% nitro 20% oil. If the muffler holds it back too much I will order up one of those blue Jett mufflers from Horizon. My goal is to have my 7lb Kaos doing vertical rolls out of sight.