I have a K&N filter and a Aaen Pipe and silencer and stock jetting.. I checked my plug yesterday and its still black..I'm not sure what the stock jetting is but people have told me to go with a 150 main will this work?

 

if its not too wet i'd leave it alone. a nice all around slight black plug is perfect. why would you want to run it lean? it'l run hotter and it'l have less power too.

 

stock jet is a #130. w/a pipe and k&n filter you should jet up a little, but the plug is the best way too tell it its lean. remeber the colder it is the leaner it will run.

 

I have a 01 trailblazer, with a polaris pipe and clutch kit, I have a uni air filter and for the winter i run a 180 jet, but it in the summer i run a 160..