what main jet should i use for a blaster with the air box lid removed,a UNI FILTER, and the spark arrester out of the stock silencer, should i change the pilot jet too

 

No one will be able to tell you that on this site. There are just too many factors that come in to play-temperature, elevation, mods, etc... But, when I put on multiple mods at one time, I just think about what that mod will do. If it increases air flow I go up one size at a time and I do the opposite when it decreases air flow. Just start off with the jets that you used before, do a plug chop, and change jets accordingly. Good Luck!